Fish symptom library

Why does my fish look dusty, gold or velvet-coated?

A fine gold, rust or dusty sheen can point toward velvet parasites, but lighting, mucus and skin damage can look similar.

Why is my fish producing excess slime or mucus?

A heavier slime coat is a general irritation response, not a single disease.

Why is my fish skin peeling or sloughing?

Sloughing skin means the protective barrier is badly compromised and can follow parasites, toxins or severe infection.

What causes white or grey patches on fish skin?

Pale patches can come from mucus, bacterial disease, parasites, water mould, injury or colour change.

Why does my fish have new black spots or dark patches?

New dark pigment can be a healing response, parasite-associated pigmentation, stress colour or a true mass.

Why does my fish have red streaks or bleeding under the skin?

Red streaks and petechiae signal tissue or blood-vessel damage but do not identify the cause by themselves.

What are tiny white bumps on fish that are not classic ich?

White bumps can be normal anatomy or several different diseases, so size, location and progression matter.

Why does my fish have cauliflower-like growths?

Cauliflower-like nodules commonly suggest lymphocystis but tumours, pox-like lesions and chronic inflammation can resemble it.

Why does my fish have a lump or mass?

A persistent lump may be a tumour, cyst, abscess, granuloma, retained eggs or internal organ enlargement.

Why are pits or holes forming in my fish’s head?

Head pits are a syndrome with several possible contributors and should not automatically be labelled Hexamita.

Why is my fish developing a curved or bent spine?

A spinal curve can be congenital, nutritional, traumatic or associated with chronic disease.

Why is my fish losing weight quickly?

Rapid weight loss means energy intake or absorption is not matching demand and can accompany serious disease.

Why is my fish getting skinny even though it still eats?

Good appetite with continued wasting raises concern for intestinal disease, parasites, malabsorption or severe competition.

Why is my fish vent red or swollen?

A red or swollen vent can follow irritation, parasites, constipation, prolapse or systemic intestinal disease.

What are red worms protruding from my fish’s anus?

Red thread-like worms protruding from the vent strongly suggest intestinal nematodes such as Camallanus.

Why is tissue protruding from my fish’s vent?

A prolapse is exposed tissue, not a worm, and may follow straining, intestinal disease, egg problems or severe swelling.

Why are my fish gills pale?

Pale gills can reflect anaemia, blood loss, severe chronic disease or sometimes normal variation.

Why are my fish gills brown, black or discoloured?

Dark or brown gill tissue can follow chemical injury, necrosis, debris or pigment change and cannot be diagnosed by colour alone.

Why is my fish breathing with only one gill?

Uneven gill movement can reflect local obstruction, injury, parasites or severe irritation on one side.

Why are my fish holding their gill covers flared?

Persistently flared opercula can signal respiratory stress, irritation or structural damage.

Why does my fish keep coughing or flicking its gills?

Fish can make repeated gill-clearing movements when the gills are irritated or obstructed.

Why is my fish spinning or corkscrewing?

Spinning is a neurologic or balance sign with many possible causes, some of them reportable in susceptible species.

Why is my fish suddenly darting around the tank?

Sudden darting may be irritation, fear, electrical/chemical disturbance or neurologic disease.

Why is my fish headstanding or holding its tail up?

Abnormal posture can come from buoyancy problems, weakness, gut distension or neurologic disease.

Why is my fish rolling or unable to stay upright?

Loss of balance is a serious nonspecific sign involving buoyancy, nervous system, weakness or toxins.

Why is my fish twitching or shaking?

Twitching may reflect irritation, courtship or dominance displays, or abnormal neuromuscular activity.

Why has my fish suddenly turned much darker?

Rapid darkening is a common stress or illness response in many species but can also be normal signalling.

Why is my fish losing scales?

Scale loss commonly follows trauma or aggression but parasites and skin disease can make scales detach more easily.

Why are my fish fins frayed or splitting?

Frayed fins can be mechanical damage, biting or progressive tissue disease.

Why are the bases of my fish’s fins red?

Redness at fin bases can be irritation, trauma or part of systemic haemorrhagic disease.

Why is my fish’s mouth stuck open?

An open mouth can result from injury, dislocation, swelling, obstruction or severe respiratory distress.

Why does my fish take food then spit it out?

Spitting food may be normal tasting behaviour or signal mouth pain, unsuitable food, gill stress or internal illness.

Why does my fish have a sunken belly?

A hollow abdomen usually indicates loss of body condition rather than a single parasite diagnosis.

Why does my fish have blood in or around the eye?

Eye haemorrhage can follow trauma, pressure, severe systemic disease or blood-vessel injury.

Why does my fish look unusually pale and weak?

General pallor can be stress colour loss, anaemia or chronic illness and needs context.

Why does my fish have smooth waxy patches on the skin?

Smooth wax-like plaques are classically associated with carp pox in koi/carp but other growths can resemble them.

Why did several fish get sick after I added new fish?

A cluster after a new arrival can reflect an introduced pathogen, transport stress or a water/stocking change.

What can cause many fish to die suddenly at the same time?

When many fish collapse together, environmental and toxic causes must be checked before assuming an infectious disease.

Why do fish keep dying one by one over several weeks?

Slow recurring losses often need a timeline and diagnostics because chronic pathogens and husbandry problems can look alike.

Why are there white spots or excess mucus on my fish’s gills?

White material or excess mucus on the gills is a respiratory warning sign, but several parasites, infections and irritants can produce a similar appearance.

Why is my fish gasping when ammonia and nitrite are normal?

Normal ammonia and nitrite do not rule out low oxygen, gill disease, chlorine/chloramine, temperature stress or other respiratory problems.

Why do my fish’s gills look swollen?

Swollen gill tissue can result from parasites, infection, chemical injury, chronic irritation or environmental stress.

Why are my fish’s gills covered in mucus?

Excess gill mucus is a protective response to irritation and is not specific to one parasite or disease.

Why do my fish have white tips on the gills?

White gill tips can reflect damaged or necrotic tissue, mucus, parasites or healing injury and need close inspection.

Why do my fish’s gill filaments look shortened or eroded?

Loss of normal gill filament structure suggests significant gill injury and can have infectious or environmental causes.

Why are my fish’s gills bleeding?

Visible gill bleeding can follow trauma, severe irritation, parasites or systemic haemorrhagic disease.

Why does my fish keep yawning or stretching its mouth?

Repeated mouth opening can be normal occasionally but frequent “yawning” may accompany gill irritation, respiratory stress or oral problems.

Why are my fish’s mouth and lips red?

Red lips or mouth tissue can result from abrasion, aggression, infection, chemical irritation or systemic haemorrhage.

Why is my fish’s mouth eroding or ulcerated?

Mouth erosion is tissue damage, not a single diagnosis, and may involve trauma plus secondary infection.

Why are my fish’s lips swollen?

Lip swelling can be caused by injury, infection, embedded material, chronic rubbing or a mass.

Why has my fish developed a crooked or deformed jaw?

Jaw deformity can be developmental, traumatic, nutritional, infectious or related to abnormal bone growth.

Why is only one of my fish’s eyes bulging?

One-sided exophthalmia often points more strongly to local trauma or infection than a whole-body fluid problem.

Why are both of my fish’s eyes bulging?

Bilateral exophthalmia can accompany systemic infection, fluid imbalance, severe environmental stress or gas supersaturation.

Why is the pupil or lens inside my fish’s eye cloudy?

Cloudiness inside the eye differs from surface haze and can reflect cataract, trauma, nutrition or internal eye disease.

Why is there a white film over my fish’s eye?

A white surface film may be mucus, corneal injury, infection or chemical irritation rather than a lens cataract.

What should I do if my fish has an injured or missing eye?

Fish can survive significant eye injury, but water quality, bleeding, infection risk and the cause of trauma need attention.

What is the worm or moving object in my fish’s eye?

Visible material in or around an eye can be a parasite, damaged tissue or debris and should not be pulled out blindly.

Why does my fish have a saddle-shaped patch across its back?

A saddleback lesion is classically associated with some bacterial skin disease but trauma and other infections can look similar.

Why does my fish have a grey or blue haze over its skin?

A grey-blue skin film often reflects excess mucus or surface injury and has many possible causes.

Why does my fish’s skin look burned or raw?

Red raw skin can follow chemical injury, severe water-quality damage, abrasion or aggressive infection.

Why does my fish have tiny red pinprick spots?

Pinpoint haemorrhages can be caused by systemic infection, trauma, toxins or severe stress and are not disease-specific.

Why does my fish have purple or bruised-looking patches?

Dark purple or bruised areas may represent haemorrhage, trauma, inflammation or colour change over damaged tissue.

Why are only a few scales raised on my fish?

Localised scale lifting differs from whole-body pineconing and more often suggests focal swelling, trauma or a lesion underneath.

Why does my fish have blister-like bubbles or vesicles on the skin?

True blisters are uncommon and can be confused with gas bubbles, cysts, parasites or swollen tissue.

Why are there bubbles under my fish’s skin or fins?

Gas visible under skin or fins raises concern for gas supersaturation but cysts and other lesions can mimic bubbles.

Why are strings of mucus hanging from my fish’s body?

Stringy skin mucus signals marked irritation and can accompany parasites, chemical injury or severe skin disease.

Why does my fish have holes or pinholes in its fins?

Small fin holes may start with mechanical damage, fin biting, water-quality stress or early tissue disease.

Why are the edges of my fish’s fins turning white or opaque?

White fin edges can represent regrowth, mucus, necrosis or infection; the direction of change matters.

Why are my fish’s fin edges turning black or dark?

Dark fin edges may be pigment during healing, necrotic tissue, ammonia-related damage or normal colour change.

Why is my fish’s tail disappearing quickly?

Rapid tail erosion is more concerning than a stable tear and can reflect severe bacterial disease, aggression or ongoing environmental injury.

Why is my fish holding only one fin clamped?

A single clamped fin suggests local pain, injury or irritation more than a whole-body stress response.

Why is only one side of my fish’s belly swollen?

Asymmetric abdominal swelling is more suggestive of a focal mass, organ enlargement, egg/reproductive problem or local lesion than simple overfeeding.

Why does my fish’s belly look red or translucent?

A red or translucent abdomen can reflect thin body wall, internal haemorrhage, inflammation or severe systemic disease.

Why is there blood or mucus in my fish’s faeces?

Blood or heavy mucus in faeces points to intestinal irritation and needs more attention than colour alone.

Why are worms or segments coming out in my fish’s faeces?

Visible worm-like material can be nematodes, tapeworm segments, mucus or food material and identification matters before treatment.

Why is undigested food coming out in my fish’s faeces?

Recognisable food in faeces can reflect overfeeding, poor digestion, inappropriate diet, intestinal disease or rapid gut transit.

Why does my fish swallow food and then bring it back up?

Regurgitation differs from simply spitting a food item and can involve oral, pharyngeal, gastrointestinal or systemic disease.

Why does my fish have trouble swallowing food?

Difficulty swallowing can follow mouth injury, jaw deformity, obstruction, gill/oral disease or neurologic problems.

Why is my fish suddenly bumping into things like it cannot see?

Sudden apparent blindness can come from eye injury, cataract, parasites, neurologic disease or severe water/chemical events.

Why does my fish keep missing food when it tries to eat?

Repeatedly missing food may indicate reduced vision, depth-perception problems, mouth dysfunction or neurologic disease.

Why does my fish sink whenever it stops swimming?

Excess negative buoyancy can involve swim-bladder dysfunction, body condition, internal disease or normal species anatomy.

Why is my fish floating uncontrollably at the surface?

Persistent uncontrolled positive buoyancy can follow swim-bladder problems, intestinal gas, internal masses or injury.

Why can’t my fish rise from the bottom?

A fish that tries but cannot rise may have buoyancy failure, profound weakness, neurologic disease or severe respiratory/systemic illness.

Why is my fish swimming backwards?

Brief backward movement can be normal in some situations, but persistent backward swimming may indicate neurologic, vestibular or severe stress problems.

Why is my fish having tremors or seizure-like episodes?

Tremors and seizure-like movement can arise from toxins, extreme water chemistry, neurologic infection, temperature shock or severe systemic disease.

Why are all my fish suddenly hyperactive or panicking?

Sudden whole-tank panic is often environmental or chemical until proven otherwise.

Why did my fish become lethargic after a water change?

A close timing relationship to a water change raises concern for temperature, pH, chlorine/chloramine, dissolved-gas or contaminant problems.

Why do my fish crowd the surface mostly at night?

Night-time surface crowding can occur when oxygen falls after lights-out, especially in heavily planted or biologically loaded systems.

Why are my fish gathering around the filter outlet?

Fish may seek a filter outlet for higher oxygen or flow, but species preference and irritation can also influence the behaviour.

Why did my fish get worse after I added medication?

Deterioration after medication may reflect drug sensitivity, oxygen reduction, overdose, interaction, wrong diagnosis or the disease progressing independently.

Why are my fish gasping after a water change?

The timing makes the replacement water, conditioner dose, temperature and gas exchange the first things to check.

Why are my fish flashing after a water change?

When flashing starts within minutes to hours of a water change, test the new water and tank chemistry before assuming parasites.

Why did fish die soon after a water change?

Reconstruct exactly what changed: source water, conditioner, temperature, volume, substrate disturbance and equipment state.

Why are my fish sick after I cleaned the filter?

Test ammonia and nitrite and confirm the filter is actually moving water and media was not exposed to untreated tap water.

Why did fish die after I cleaned the filter?

A filter-cleaning link points first to ammonia, nitrite, oxygen and chemical exposure rather than a new contagious disease.

Why are my fish gasping after a power outage?

Duration of the outage, stocking density and whether filtration/aeration restarted normally are key clues.

Why are my fish sick after the heater failed?

Check the actual minimum/maximum water temperature rather than relying only on the heater setting.

Why are my fish sick after the tank overheated?

Temperature and oxygen must be interpreted together because warm water holds less oxygen and can increase ammonia toxicity.

Why are my fish sick after CO2 injection?

Turn attention to CO2 delivery, pH trend and fish respiratory behaviour before adding medication.

Why are my fish sick after I added salt?

Measure salinity/conductivity and verify the actual amount added and total water volume.

Why are my fish sick after adding water conditioner?

Verify the exact product, dose and source-water chlorine/chloramine rather than assuming all conditioners behave the same.

Why are my fish sick after moving the aquarium?

Moving can create several simultaneous stresses, so compare old versus new water and confirm filter function.

Why are my fish sick after transport?

Separate transport stress from contagious disease by checking the timeline and whether only transported fish are affected.

Why are my fish sick after a very large feeding?

Test water and check whether uneaten food remains; a shared response in many fish points toward the system rather than one fish’s gut.

Why are my fish sick after eating live food?

Record the live-food source and whether only fish that ate it are affected; preserve a sample if a veterinarian may investigate.

Why are my fish sick after adding new decoration?

Remove suspicion from infection until the material, coating and water chemistry have been checked.

Why are my fish sick after spray cleaner or aerosol was used nearby?

The exposure timing and whether the aquarium was uncovered are key; ordinary aquarium tests may not detect the contaminant.

Why are my fish sick after a metal object was put in the tank?

Identify the metal and test water where possible; toxicity changes with hardness, alkalinity and pH.

Why are my fish sick after I disturbed the substrate?

A close timing link to deep substrate disturbance makes environmental causes more likely than a new infection.

Why are my fish sick after a deep gravel clean?

Check water immediately and compare how much substrate/filter media was disturbed in the same session.

Why are my fish gills red and inflamed?

Redness alone cannot identify the cause; combine water tests with gill movement and wet-mount findings if disease persists.

Why is stringy mucus hanging from my fish gills?

Confirm that the material originates from gill tissue rather than food/debris and test ammonia, nitrite and chlorine.

Why is my fish rubbing mostly around its gills?

Gill-focused rubbing increases suspicion of a gill problem but does not distinguish parasite from chemical irritation.

Why is my fish mouth bleeding?

Look for a clear injury point and compare whether other fish have mouth lesions or systemic haemorrhage.

Why is my fish jaw swollen?

A one-sided firm swelling suggests a different differential from diffuse soft swelling in several fish.

Why are my fish lips turning white?

Check whether the white area is smooth pigment, eroded tissue or a raised growth and compare progression over 24–48 hours.

Why are my fish nostrils red or swollen?

Examine both sides and review recent netting, transport and aggression before assuming systemic disease.

Why is my fish head swollen?

Location and texture matter: diffuse symmetrical swelling differs from a single firm mass.

Why do my fish eyes look sunken?

Compare body condition and both eyes; sunken eyes in a very thin fish suggests a different process from a local eye injury.

Why is one fish eye red or inflamed?

One-eye disease often points toward local trauma or infection, while both eyes in many fish raises environmental/systemic causes.

Why does my fish body look milky or cloudy?

View under neutral lighting and check whether the haze wipes/changes with angle or is true skin/mucus change.

Why does my fish ulcer have a white edge?

A white rim is not enough to identify fungus; look for tissue loss, fuzzy growth, haemorrhage and progression.

Why is my fish developing several skin ulcers?

Multiple expanding ulcers shift concern toward systemic or transmissible disease rather than one collision.

Why are the fin rays on my fish exposed?

Check whether the damage is progressing between photos and whether other fish are nipping.

Why are my fish fins curling or deforming?

New deformity in an adult has a different differential from a stable juvenile or breed-related shape.

Why is the webbing between my fish fin rays disappearing?

Smooth missing webbing after aggression differs from progressively necrotic or reddened tissue.

Why does my fish belly feel or look firm and hard?

Do not squeeze the fish; imaging is often safer and more informative than trying to diagnose firmness by touch.

Why does my fish bloat immediately after eating?

A swelling that resolves between meals differs from progressive enlargement unrelated to feeding.

Why is my fish not passing faeces?

First confirm the fish is actually eating; absence of faeces in a fasting fish is not the same as obstruction.

Why does my fish have long white stringy faeces?

White stringy material is not proof of internal parasites; appetite, body condition and microscopy matter.

Why are my fish faeces unusually pale or white?

Compare with the food colour and whether the fish is eating normally before attributing pale faeces to a pathogen.

Why do my fish faeces float?

Floating faeces by itself is weak evidence; pair it with appetite, weight trend and stool appearance.

Why do my fish faeces look oily or leave a film?

Review the diet and food freshness and check whether an oily film also appears when food is added directly to water.

Why is my fish swimming head-up with its tail down?

Observe whether the posture changes when the fish stops swimming and whether the abdomen is enlarged.

Why is my fish lying on its side but still breathing?

Check water and temperature immediately before assuming swim-bladder disease.

Why does my fish rest on the bottom after feeding?

Compare with the species’ normal behaviour and whether the sign occurs only after large meals.

Why is my fish suddenly jumping out of the water?

If several fish jump or dart at once, environmental irritation moves higher than one fish being startled.

Why is my fish hiding beside the heater?

Measure temperature at several tank locations and compare heater operation with species requirements.

Why are my fish clustering around the air stone?

When many fish cluster at the aeration source, test oxygen-related causes before calling it normal behaviour.

Why are the largest fish piping at the surface first?

Large fish becoming distressed before small fish is a classic clue for declining dissolved oxygen, especially overnight or in warm water.

Why is only one fish breathing fast?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish breathing fast after feeding?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish breathing fast after medication?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish gasping early in the morning?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why do my fish improve when I add more aeration?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why do my fish improve after a water change and then relapse?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why do my fish symptoms get worse overnight?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why do my fish show symptoms after the lights come on?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why did my fish suddenly stop eating?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish refusing food but otherwise acting normal?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is one fish isolating itself from the school?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish hiding all day?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish staying at the surface without gasping?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish resting on plants or leaves?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish hanging near the filter intake?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are only my bottom-dwelling fish getting sick?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are only the largest fish affected?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are only the new fish getting sick?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is only one fish sick when the rest look normal?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why did my fish recover during treatment and then relapse?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why did fish symptoms return days after treatment ended?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after adding new plants?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after adding plant fertiliser?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after using an algaecide?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after hydrogen peroxide treatment?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after formalin treatment?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after copper medication?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after antibiotic treatment?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after anti-parasite treatment?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after a salt bath?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after acclimation?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after eating frozen food?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish sick after eating thawed food left out too long?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish tail split without obvious fin rot?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is one of my fish fins not moving normally?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish shedding slime or mucus in sheets?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why can I see red lines or veins under my fish skin?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why did black marks appear after an ammonia problem?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why did white patches appear after treatment?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is only one gill swollen?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why do my fish gill tips look curled or distorted?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why did my fish eye turn cloudy after an injury?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are both of my fish eyes becoming cloudy inside the lens?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish bloated without raised scales?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish abdomen swelling rapidly over a few hours?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why did my fish spine suddenly become bent?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why has my fish had a bent spine since it was young?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why are my fish fry developing bent spines?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why can’t my fish fry inflate their swim bladder?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish shimmying or rocking in place?

Use timing, water tests and related signs to investigate this symptom without treating it as a diagnosis.

Why is my fish sick after spawning?

Use timing, water tests and related signs to investigate why is my fish sick after spawning without treating the symptom as a diagnosis.

Why is my fish breathing fast after spawning?

Use timing, water tests and related signs to investigate why is my fish breathing fast after spawning without treating the symptom as a diagnosis.

Why did my fish stop eating after spawning?

Use timing, water tests and related signs to investigate why did my fish stop eating after spawning without treating the symptom as a diagnosis.

Why is my fish’s vent swollen after spawning?

Use timing, water tests and related signs to investigate why is my fish’s vent swollen after spawning without treating the symptom as a diagnosis.

Why is my fish bleeding after spawning?

Use timing, water tests and related signs to investigate why is my fish bleeding after spawning without treating the symptom as a diagnosis.

Why is my fish losing balance after spawning?

Use timing, water tests and related signs to investigate why is my fish losing balance after spawning without treating the symptom as a diagnosis.

Why is my female fish still swollen after spawning?

Use timing, water tests and related signs to investigate why is my female fish still swollen after spawning without treating the symptom as a diagnosis.

Why does my fish still look full of eggs after a partial spawn?

Use timing, water tests and related signs to investigate why does my fish still look full of eggs after a partial spawn without treating the symptom as a diagnosis.

Why is my male fish injured after spawning?

Use timing, water tests and related signs to investigate why is my male fish injured after spawning without treating the symptom as a diagnosis.

Why is my female fish injured after spawning?

Use timing, water tests and related signs to investigate why is my female fish injured after spawning without treating the symptom as a diagnosis.

Why do my breeding fish keep getting sick after every spawn?

Use timing, water tests and related signs to investigate why do my breeding fish keep getting sick after every spawn without treating the symptom as a diagnosis.

Why did my fish stop releasing eggs mid-spawn?

Use timing, water tests and related signs to investigate why did my fish stop releasing eggs mid-spawn without treating the symptom as a diagnosis.

Why does my fish have tissue protruding after spawning?

Use timing, water tests and related signs to investigate why does my fish have tissue protruding after spawning without treating the symptom as a diagnosis.

Why does my fish have long stringy faeces after spawning?

Use timing, water tests and related signs to investigate why does my fish have long stringy faeces after spawning without treating the symptom as a diagnosis.

Why does my fish’s abdomen look firm or tight after spawning?

Use timing, water tests and related signs to investigate why does my fish’s abdomen look firm or tight after spawning without treating the symptom as a diagnosis.

Why are my fry dying within 24 hours of hatching?

Use timing, water tests and related signs to investigate why are my fry dying within 24 hours of hatching without treating the symptom as a diagnosis.

Why are my fry dying two to seven days after hatching?

Use timing, water tests and related signs to investigate why are my fry dying two to seven days after hatching without treating the symptom as a diagnosis.

Why are my fry dying as the yolk sac is absorbed?

Use timing, water tests and related signs to investigate why are my fry dying as the yolk sac is absorbed without treating the symptom as a diagnosis.

Why do my fry die after first feeding?

Use timing, water tests and related signs to investigate why do my fry die after first feeding without treating the symptom as a diagnosis.

Why won’t my fry start feeding?

Use timing, water tests and related signs to investigate why won’t my fry start feeding without treating the symptom as a diagnosis.

Why is my fry’s yolk sac swollen?

Use timing, water tests and related signs to investigate why is my fry’s yolk sac swollen without treating the symptom as a diagnosis.

Why is my fry’s yolk sac not shrinking?

Use timing, water tests and related signs to investigate why is my fry’s yolk sac not shrinking without treating the symptom as a diagnosis.

Why is my fry’s yolk sac red or haemorrhagic?

Use timing, water tests and related signs to investigate why is my fry’s yolk sac red or haemorrhagic without treating the symptom as a diagnosis.

Why is my fry’s yolk sac cloudy or opaque?

Use timing, water tests and related signs to investigate why is my fry’s yolk sac cloudy or opaque without treating the symptom as a diagnosis.

Why are my fry lying on the bottom after hatching?

Use timing, water tests and related signs to investigate why are my fry lying on the bottom after hatching without treating the symptom as a diagnosis.

Why are my fry stuck or floating at the surface after hatching?

Use timing, water tests and related signs to investigate why are my fry stuck or floating at the surface after hatching without treating the symptom as a diagnosis.

Why can’t my fry stay upright?

Use timing, water tests and related signs to investigate why can’t my fry stay upright without treating the symptom as a diagnosis.

Why do my fry sink after they start swimming?

Use timing, water tests and related signs to investigate why do my fry sink after they start swimming without treating the symptom as a diagnosis.

Why are my fry growing at very different rates?

Use timing, water tests and related signs to investigate why are my fry growing at very different rates without treating the symptom as a diagnosis.

Why are some fry stunted while the others grow?

Use timing, water tests and related signs to investigate why are some fry stunted while the others grow without treating the symptom as a diagnosis.

Why do my fry have swollen bellies?

Use timing, water tests and related signs to investigate why do my fry have swollen bellies without treating the symptom as a diagnosis.

Why are my fry suddenly dying in large numbers?

Use timing, water tests and related signs to investigate why are my fry suddenly dying in large numbers without treating the symptom as a diagnosis.

Why do fry die after moving to a grow-out tank?

Use timing, water tests and related signs to investigate why do fry die after moving to a grow-out tank without treating the symptom as a diagnosis.

Why are my fry’s gill covers short or deformed?

Use timing, water tests and related signs to investigate why are my fry’s gill covers short or deformed without treating the symptom as a diagnosis.

Why does fry growth stall after weaning onto a new food?

Use timing, water tests and related signs to investigate why does fry growth stall after weaning onto a new food without treating the symptom as a diagnosis.

Why do fish eggs turn white before hatching?

Use timing, water tests and related signs to investigate why do fish eggs turn white before hatching without treating the symptom as a diagnosis.

Why are fish embryos dying before hatching?

Use timing, water tests and related signs to investigate why are fish embryos dying before hatching without treating the symptom as a diagnosis.

Why do fry die after weaning from live food?

Use timing, water tests and related signs to investigate why do fry die after weaning from live food without treating the symptom as a diagnosis.

Why are my fish sick after a filter failure?

Use timing, water tests and related signs to investigate why are my fish sick after a filter failure without treating the symptom as a diagnosis.

Why are my fish getting sick days after a power outage?

Use timing, water tests and related signs to investigate why are my fish getting sick days after a power outage without treating the symptom as a diagnosis.

Why are my fish sick after a pH swing?

Use timing, water tests and related signs to investigate why are my fish sick after a ph swing without treating the symptom as a diagnosis.

Why are my fish sick after adding a buffer?

Use timing, water tests and related signs to investigate why are my fish sick after adding a buffer without treating the symptom as a diagnosis.

Why are my fish sick after remineralising the water?

Use timing, water tests and related signs to investigate why are my fish sick after remineralising the water without treating the symptom as a diagnosis.

Why are my fish sick after switching to RO water?

Use timing, water tests and related signs to investigate why are my fish sick after switching to ro water without treating the symptom as a diagnosis.

Why are my fish sick after changing food?

Use timing, water tests and related signs to investigate why are my fish sick after changing food without treating the symptom as a diagnosis.

Why is my fish sick after fasting?

Use timing, water tests and related signs to investigate why is my fish sick after fasting without treating the symptom as a diagnosis.

Why are my fish sick after adding many fish at once?

Use timing, water tests and related signs to investigate why are my fish sick after adding many fish at once without treating the symptom as a diagnosis.

Why are my fish sick after replacing filter media?

Use timing, water tests and related signs to investigate why are my fish sick after replacing filter media without treating the symptom as a diagnosis.

Why do my fish’s symptoms come and go?

Use timing, water tests and related signs to investigate why do my fish’s symptoms come and go without treating the symptom as a diagnosis.

Why does only one fish species keep getting sick in my tank?

Use timing, water tests and related signs to investigate why does only one fish species keep getting sick in my tank without treating the symptom as a diagnosis.

Why are my fish sick after a canister filter lost prime?

Use timing, water tests and related signs to investigate why are my fish sick after a canister filter lost prime? without treating the event as a diagnosis.

Why are my fish sick after restarting a canister filter that held stagnant water?

Use timing, water tests and related signs to investigate why are my fish sick after restarting a canister filter that held stagnant water? without treating the event as a diagnosis.

Why are my fish sick after the return pump stopped?

Use timing, water tests and related signs to investigate why are my fish sick after the return pump stopped? without treating the event as a diagnosis.

Why are my fish sick after the aquarium overflow became blocked?

Use timing, water tests and related signs to investigate why are my fish sick after the aquarium overflow became blocked? without treating the event as a diagnosis.

Why are my fish sick after a wavemaker stopped?

Use timing, water tests and related signs to investigate why are my fish sick after a wavemaker stopped? without treating the event as a diagnosis.

Why are my fish sick after wavemaker flow was increased?

Use timing, water tests and related signs to investigate why are my fish sick after wavemaker flow was increased? without treating the event as a diagnosis.

Why are my fish sick after a sponge filter became clogged?

Use timing, water tests and related signs to investigate why are my fish sick after a sponge filter became clogged? without treating the event as a diagnosis.

Why are my fish sick after a prefilter became clogged?

Use timing, water tests and related signs to investigate why are my fish sick after a prefilter became clogged? without treating the event as a diagnosis.

Why are my fish sick after the water level dropped below the filter intake?

Use timing, water tests and related signs to investigate why are my fish sick after the water level dropped below the filter intake? without treating the event as a diagnosis.

Why are my fish sick after replacing a UV sterilizer bulb?

Use timing, water tests and related signs to investigate why are my fish sick after replacing a uv sterilizer bulb? without treating the event as a diagnosis.

Why are my fish sick after adding zeolite?

Use timing, water tests and related signs to investigate why are my fish sick after adding zeolite? without treating the event as a diagnosis.

Why are my fish sick after adding peat?

Use timing, water tests and related signs to investigate why are my fish sick after adding peat? without treating the event as a diagnosis.

Why are my fish sick after adding botanical leaves or pods?

Use timing, water tests and related signs to investigate why are my fish sick after adding botanical leaves or pods? without treating the event as a diagnosis.

Why are my fish sick after using blackwater extract?

Use timing, water tests and related signs to investigate why are my fish sick after using blackwater extract? without treating the event as a diagnosis.

Why are my fish sick after adding a sludge-remover or enzyme product?

Use timing, water tests and related signs to investigate why are my fish sick after adding a sludge-remover or enzyme product? without treating the event as a diagnosis.

Why are my fish sick after adding nitrate-remover resin?

Use timing, water tests and related signs to investigate why are my fish sick after adding nitrate-remover resin? without treating the event as a diagnosis.

Why are my fish sick after adding ion-exchange resin?

Use timing, water tests and related signs to investigate why are my fish sick after adding ion-exchange resin? without treating the event as a diagnosis.

Why are my fish sick after dosing iodine?

Use timing, water tests and related signs to investigate why are my fish sick after dosing iodine? without treating the event as a diagnosis.

Why are my fish sick after dosing trace elements?

Use timing, water tests and related signs to investigate why are my fish sick after dosing trace elements? without treating the event as a diagnosis.

Why are my fish sick after dosing iron?

Use timing, water tests and related signs to investigate why are my fish sick after dosing iron? without treating the event as a diagnosis.

Why are my fish sick after dosing potassium?

Use timing, water tests and related signs to investigate why are my fish sick after dosing potassium? without treating the event as a diagnosis.

Why are my fish sick after a CO2 solenoid stuck open?

Use timing, water tests and related signs to investigate why are my fish sick after a co2 solenoid stuck open? without treating the event as a diagnosis.

Why are my fish sick after the aquarium lights were left on overnight?

Use timing, water tests and related signs to investigate why are my fish sick after the aquarium lights were left on overnight? without treating the event as a diagnosis.

Why are my fish sick after the aquarium lights stayed off for several days?

Use timing, water tests and related signs to investigate why are my fish sick after the aquarium lights stayed off for several days? without treating the event as a diagnosis.

Why are my fish sick after light intensity was increased?

Use timing, water tests and related signs to investigate why are my fish sick after light intensity was increased? without treating the event as a diagnosis.

Why are my fish sick after the photoperiod was lengthened?

Use timing, water tests and related signs to investigate why are my fish sick after the photoperiod was lengthened? without treating the event as a diagnosis.

Why are my fish sick after the aquarium was covered tightly?

Use timing, water tests and related signs to investigate why are my fish sick after the aquarium was covered tightly? without treating the event as a diagnosis.

Why are my fish sick after using a new bucket or container?

Use timing, water tests and related signs to investigate why are my fish sick after using a new bucket or container? without treating the event as a diagnosis.

Why are my fish sick after detergent residue got onto aquarium equipment?

Use timing, water tests and related signs to investigate why are my fish sick after detergent residue got onto aquarium equipment? without treating the event as a diagnosis.

Why are my fish sick after using bleach-disinfected equipment?

Use timing, water tests and related signs to investigate why are my fish sick after using bleach-disinfected equipment? without treating the event as a diagnosis.

Why are my fish sick after cleaning equipment with vinegar or citric acid?

Use timing, water tests and related signs to investigate why are my fish sick after cleaning equipment with vinegar or citric acid? without treating the event as a diagnosis.

Why are my fish sick after hand sanitiser got into the aquarium?

Use timing, water tests and related signs to investigate why are my fish sick after hand sanitiser got into the aquarium? without treating the event as a diagnosis.

Why are my fish sick after sunscreen or insect repellent contaminated the water?

Use timing, water tests and related signs to investigate why are my fish sick after sunscreen or insect repellent contaminated the water? without treating the event as a diagnosis.

Why are my pond fish sick after heavy rain?

Use timing, water tests and related signs to investigate why are my pond fish sick after heavy rain? without treating the event as a diagnosis.

Why are my pond fish sick after a pond turnover?

Use timing, water tests and related signs to investigate why are my pond fish sick after a pond turnover? without treating the event as a diagnosis.

Why are my pond fish sick after roof runoff entered the pond?

Use timing, water tests and related signs to investigate why are my pond fish sick after roof runoff entered the pond? without treating the event as a diagnosis.

Why are my pond fish sick after fertiliser runoff entered the pond?

Use timing, water tests and related signs to investigate why are my pond fish sick after fertiliser runoff entered the pond? without treating the event as a diagnosis.

Why are my pond fish sick after herbicide drift near the pond?

Use timing, water tests and related signs to investigate why are my pond fish sick after herbicide drift near the pond? without treating the event as a diagnosis.

Why are my pond fish sick after pool or spa water entered the pond?

Use timing, water tests and related signs to investigate why are my pond fish sick after pool or spa water entered the pond? without treating the event as a diagnosis.

Why are my pond fish sick after wildfire smoke or ash reached the pond?

Use timing, water tests and related signs to investigate why are my pond fish sick after wildfire smoke or ash reached the pond? without treating the event as a diagnosis.

Why are my marine fish sick after coral dip entered the tank?

Use timing, water tests and related signs to investigate why are my marine fish sick after coral dip entered the tank? without treating the event as a diagnosis.

Why are my marine fish sick after adding new coral frags?

Use timing, water tests and related signs to investigate why are my marine fish sick after adding new coral frags? without treating the event as a diagnosis.

Why are my marine fish sick after adding live rock?

Use timing, water tests and related signs to investigate why are my marine fish sick after adding live rock? without treating the event as a diagnosis.

Why are my marine fish sick after adding dry rock?

Use timing, water tests and related signs to investigate why are my marine fish sick after adding dry rock? without treating the event as a diagnosis.

Why are my marine fish sick after switching to a new salt-mix batch?

Use timing, water tests and related signs to investigate why are my marine fish sick after switching to a new salt-mix batch? without treating the event as a diagnosis.

Why are my marine fish sick after incompletely mixed saltwater was added?

Use timing, water tests and related signs to investigate why are my marine fish sick after incompletely mixed saltwater was added? without treating the event as a diagnosis.

Why are my marine fish sick after a refractometer was miscalibrated?

Use timing, water tests and related signs to investigate why are my marine fish sick after a refractometer was miscalibrated? without treating the event as a diagnosis.

Why are my marine fish sick after DI resin was exhausted?

Use timing, water tests and related signs to investigate why are my marine fish sick after di resin was exhausted? without treating the event as a diagnosis.

Why are my fish sick after eating medicated food?

Use timing, water tests and related signs to investigate why are my fish sick after eating medicated food? without treating the event as a diagnosis.

Why are my fish sick after eating expired pellets?

Use timing, water tests and related signs to investigate why are my fish sick after eating expired pellets? without treating the event as a diagnosis.

Why are my fish sick after an air-line check valve was installed backwards?

Differential guide for why are my fish sick after an air-line check valve was installed backwards?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after a filter impeller jammed while the motor was running?

Differential guide for why are my fish sick after a filter impeller jammed while the motor was running?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after a filter venturi stopped drawing air?

Differential guide for why are my fish sick after a filter venturi stopped drawing air?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after the filter output was moved below the surface?

Differential guide for why are my fish sick after the filter output was moved below the surface?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after a pump developed an airlock or cavitation?

Differential guide for why are my fish sick after a pump developed an airlock or cavitation?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after power returned but the pump did not restart?

Differential guide for why are my fish sick after power returned but the pump did not restart?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after backup aeration ran out during a power outage?

Differential guide for why are my fish sick after backup aeration ran out during a power outage?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after generator exhaust entered the aquarium room?

Differential guide for why are my fish sick after generator exhaust entered the aquarium room?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after an automatic feeder jammed and stopped feeding?

Differential guide for why are my fish sick after an automatic feeder jammed and stopped feeding?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after a cooling fan failed?

Differential guide for why are my fish sick after a cooling fan failed?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after the temperature probe fell out of the water?

Differential guide for why are my fish sick after the temperature probe fell out of the water?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after relying on an inaccurate thermometer?

Differential guide for why are my fish sick after relying on an inaccurate thermometer?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after fly spray or insecticide was used nearby?

Differential guide for why are my fish sick after fly spray or insecticide was used nearby?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after an insect fogger or bug bomb was used in the room?

Differential guide for why are my fish sick after an insect fogger or bug bomb was used in the room?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after PVC cement or solvent was used on aquarium plumbing?

Differential guide for why are my fish sick after pvc cement or solvent was used on aquarium plumbing?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after an aquarium magnet started corroding?

Differential guide for why are my fish sick after an aquarium magnet started corroding?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after a metal clamp or fitting started rusting?

Differential guide for why are my fish sick after a metal clamp or fitting started rusting?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after a glass heater cracked?

Differential guide for why are my fish sick after a glass heater cracked?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after adding a 3D-printed part?

Differential guide for why are my fish sick after adding a 3d-printed part?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my pond fish sick after liner adhesive or sealant was used?

Differential guide for why are my pond fish sick after liner adhesive or sealant was used?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after eating mosquito larvae collected outdoors?

Differential guide for why are my fish sick after eating mosquito larvae collected outdoors?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after eating insects collected outdoors?

Differential guide for why are my fish sick after eating insects collected outdoors?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after frozen food thawed and was refrozen?

Differential guide for why are my fish sick after frozen food thawed and was refrozen?, with key environmental checks, look-alikes and evidence-led next steps.

Why is my fish sick after jumping out and being returned to the tank?

Differential guide for why is my fish sick after jumping out and being returned to the tank?, with key environmental checks, look-alikes and evidence-led next steps.

Why is my fish sick after being trapped behind decor or equipment?

Differential guide for why is my fish sick after being trapped behind decor or equipment?, with key environmental checks, look-alikes and evidence-led next steps.

Why is my fish sick after being pinned against a filter intake?

Differential guide for why is my fish sick after being pinned against a filter intake?, with key environmental checks, look-alikes and evidence-led next steps.

Why is my fish sick after being pulled into a siphon during a water change?

Differential guide for why is my fish sick after being pulled into a siphon during a water change?, with key environmental checks, look-alikes and evidence-led next steps.

Why is my fish sick after being dropped during transfer?

Differential guide for why is my fish sick after being dropped during transfer?, with key environmental checks, look-alikes and evidence-led next steps.

Why did a shipped fish get worse soon after the transport bag was opened?

Differential guide for why did a shipped fish get worse soon after the transport bag was opened?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after transport-bag water was poured into the aquarium?

Differential guide for why are my fish sick after transport-bag water was poured into the aquarium?, with key environmental checks, look-alikes and evidence-led next steps.

Why is my marine fish sick after a freshwater dip?

Differential guide for why is my marine fish sick after a freshwater dip?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my marine fish sick after the auto top-off stuck on?

Differential guide for why are my marine fish sick after the auto top-off stuck on?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my marine fish sick after saltwater was put in the auto top-off reservoir?

Differential guide for why are my marine fish sick after saltwater was put in the auto top-off reservoir?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my marine fish sick after refugium macroalgae died off?

Differential guide for why are my marine fish sick after refugium macroalgae died off?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my marine fish sick after the refugium light failed?

Differential guide for why are my marine fish sick after the refugium light failed?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my marine fish sick after a calcium reactor released too much CO2?

Differential guide for why are my marine fish sick after a calcium reactor released too much co2?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my marine fish sick after activated-carbon dust entered the display?

Differential guide for why are my marine fish sick after activated-carbon dust entered the display?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my marine fish sick after disturbed sand released a rotten-egg smell?

Differential guide for why are my marine fish sick after disturbed sand released a rotten-egg smell?, with key environmental checks, look-alikes and evidence-led next steps.

Why is my marine fish sick after an anemone was damaged by a powerhead?

Differential guide for why is my marine fish sick after an anemone was damaged by a powerhead?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after seashells or coral skeleton were added?

Differential guide for why are my fish sick after seashells or coral skeleton were added?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after the filter was cleaned too thoroughly?

Differential guide for why are my fish sick after the filter was cleaned too thoroughly?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after a water-change hose picked up household contamination?

Differential guide for why are my fish sick after a water-change hose picked up household contamination?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my pond fish sick after the waterfall or return stream stopped?

Differential guide for why are my pond fish sick after the waterfall or return stream stopped?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my pond fish sick after the pump intake clogged with leaves?

Differential guide for why are my pond fish sick after the pump intake clogged with leaves?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my pond fish sick after a large amount of leaf litter fell into the pond?

Differential guide for why are my pond fish sick after a large amount of leaf litter fell into the pond?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my pond fish sick after many birds began using the pond?

Differential guide for why are my pond fish sick after many birds began using the pond?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after uncured concrete or cement decor was added?

Differential guide for why are my fish sick after uncured concrete or cement decor was added?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after a fire extinguisher was discharged nearby?

Differential guide for why are my fish sick after a fire extinguisher was discharged nearby?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after second-hand equipment with unknown residues was added?

Differential guide for why are my fish sick after second-hand equipment with unknown residues was added?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after an ozone or ionising air purifier was used nearby?

Differential guide for why are my fish sick after an ozone or ionising air purifier was used nearby?, with key environmental checks, look-alikes and evidence-led next steps.

Why are my fish sick after cut flowers or florist greenery were added to the aquarium?

Differential guide for why are my fish sick after cut flowers or florist greenery were added to the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after hand soap residue entered the aquarium?

Differential guide for why are my fish sick after hand soap residue entered the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after hand lotion or moisturiser contacted the water?

Differential guide for why are my fish sick after hand lotion or moisturiser contacted the water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after pesticide-treated houseplants were handled near the aquarium?

Differential guide for why are my fish sick after pesticide-treated houseplants were handled near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after nail-polish remover or solvent fumes were used nearby?

Differential guide for why are my fish sick after nail-polish remover or solvent fumes were used nearby?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after paint fumes were present near the aquarium?

Differential guide for why are my fish sick after paint fumes were present near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after fertiliser was used on houseplants near the aquarium?

Differential guide for why are my fish sick after fertiliser was used on houseplants near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after bleach was used for cleaning near the aquarium?

Differential guide for why are my fish sick after bleach was used for cleaning near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after unknown wood or timber decor was added to the aquarium?

Differential guide for why are my fish sick after unknown wood or timber decor was added to the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a humidifier additive or fragrance was used near the aquarium?

Differential guide for why are my fish sick after a humidifier additive or fragrance was used near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after water collected from a dehumidifier was used in the aquarium?

Differential guide for why are my fish sick after water collected from a dehumidifier was used in the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after wood stain or varnish fumes were present near the aquarium?

Differential guide for why are my fish sick after wood stain or varnish fumes were present near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after mothballs or moth-repellent products were used near the aquarium?

Differential guide for why are my fish sick after mothballs or moth-repellent products were used near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after spray foam or expanding foam was curing near the aquarium?

Differential guide for why are my fish sick after spray foam or expanding foam was curing near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after soldering flux or solder fumes were produced near the aquarium?

Differential guide for why are my fish sick after soldering flux or solder fumes were produced near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a brass fitting or valve was added to aquarium plumbing?

Differential guide for why are my fish sick after a brass fitting or valve was added to aquarium plumbing?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after galvanised metal contacted aquarium water?

Differential guide for why are my fish sick after galvanised metal contacted aquarium water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after UV resin was used in or near the aquarium?

Differential guide for why are my fish sick after uv resin was used in or near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after new copper plumbing was connected to the water supply?

Differential guide for why are my fish sick after new copper plumbing was connected to the water supply?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after water was used after a hot-water cylinder flush?

Differential guide for why are my fish sick after water was used after a hot-water cylinder flush?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after water from a household softener was used?

Differential guide for why are my fish sick after water from a household softener was used?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after RO water was used without appropriate remineralisation?

Differential guide for why are my fish sick after ro water was used without appropriate remineralisation?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after DI water was used without appropriate remineralisation?

Differential guide for why are my fish sick after di water was used without appropriate remineralisation?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after an aluminium fitting or part contacted aquarium water?

Differential guide for why are my fish sick after an aluminium fitting or part contacted aquarium water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after new carbon media was added without rinsing?

Differential guide for why are my fish sick after new carbon media was added without rinsing?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after phosphate-remover dust entered the water?

Differential guide for why are my fish sick after phosphate-remover dust entered the water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after zeolite was added to the filter?

Differential guide for why are my fish sick after zeolite was added to the filter?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a coin or unknown metal object fell into the aquarium?

Differential guide for why are my fish sick after a coin or unknown metal object fell into the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after new filter floss or fabric left residue?

Differential guide for why are my fish sick after new filter floss or fabric left residue?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after new sponge or foam material was added?

Differential guide for why are my fish sick after new sponge or foam material was added?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a new rubber hose was used?

Differential guide for why are my fish sick after a new rubber hose was used?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after fibreglass dust was produced during renovation near the aquarium?

Differential guide for why are my fish sick after fibreglass dust was produced during renovation near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after ceiling or insulation dust entered the aquarium area?

Differential guide for why are my fish sick after ceiling or insulation dust entered the aquarium area?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a cleaning or vacuum hose had chemical residue?

Differential guide for why are my fish sick after a cleaning or vacuum hose had chemical residue?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after cleaner residue remained on the tank lid?

Differential guide for why are my fish sick after cleaner residue remained on the tank lid?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after carpet cleaner or carpet-cleaning solution was used in the aquarium room?

Differential guide for why are my fish sick after carpet cleaner or carpet-cleaning solution was used in the aquarium room?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after furniture polish was sprayed or used near the aquarium?

Differential guide for why are my fish sick after furniture polish was sprayed or used near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after the house was treated for pests?

Differential guide for why are my fish sick after the house was treated for pests?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after rodent bait or bait residue may have contacted the aquarium?

Differential guide for why are my fish sick after rodent bait or bait residue may have contacted the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a termite treatment was applied in or around the house?

Differential guide for why are my fish sick after a termite treatment was applied in or around the house?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a mosquito coil was used near the aquarium?

Differential guide for why are my fish sick after a mosquito coil was used near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after fog-machine smoke was used nearby?

Differential guide for why are my fish sick after fog-machine smoke was used nearby?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after construction dust entered the aquarium area?

Differential guide for why are my fish sick after construction dust entered the aquarium area?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after sawdust from renovation reached the aquarium?

Differential guide for why are my fish sick after sawdust from renovation reached the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after plaster or drywall dust reached the aquarium?

Differential guide for why are my fish sick after plaster or drywall dust reached the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after cement dust reached the aquarium?

Differential guide for why are my fish sick after cement dust reached the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after metal-grinding dust was produced nearby?

Differential guide for why are my fish sick after metal-grinding dust was produced nearby?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after welding fumes or particles were produced nearby?

Differential guide for why are my fish sick after welding fumes or particles were produced nearby?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after rust remover was used near the aquarium?

Differential guide for why are my fish sick after rust remover was used near the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after paint thinner or solvent fumes were present nearby?

Differential guide for why are my fish sick after paint thinner or solvent fumes were present nearby?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a new aquarium heater was installed?

Differential guide for why are my fish sick after a new aquarium heater was installed?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a new aquarium chiller was installed?

Differential guide for why are my fish sick after a new aquarium chiller was installed?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after the aquarium chiller stopped cooling?

Differential guide for why are my fish sick after the aquarium chiller stopped cooling?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after the chiller temperature probe was moved?

Differential guide for why are my fish sick after the chiller temperature probe was moved?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a glass aquarium thermometer broke in the tank?

Differential guide for why are my fish sick after a glass aquarium thermometer broke in the tank?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a grounding probe corroded in the aquarium?

Differential guide for why are my fish sick after a grounding probe corroded in the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a submersible aquarium light cracked or leaked?

Differential guide for why are my fish sick after a submersible aquarium light cracked or leaked?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a pump seal failed or leaked into the water?

Differential guide for why are my fish sick after a pump seal failed or leaked into the water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after pump grease or oil leaked into the aquarium?

Differential guide for why are my fish sick after pump grease or oil leaked into the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after oil from a compressed-air source reached the aquarium airline?

Differential guide for why are my fish sick after oil from a compressed-air source reached the aquarium airline?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after new airline tubing was installed?

Differential guide for why are my fish sick after new airline tubing was installed?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after the surface skimmer jammed or stopped drawing surface water?

Differential guide for why are my fish sick after the surface skimmer jammed or stopped drawing surface water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a filter bypass valve was accidentally left open?

Differential guide for why are my fish sick after a filter bypass valve was accidentally left open?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after canister-filter baskets or seals were reassembled incorrectly?

Differential guide for why are my fish sick after canister-filter baskets or seals were reassembled incorrectly?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a fine polishing pad clogged rapidly?

Differential guide for why are my fish sick after a fine polishing pad clogged rapidly?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after biological filter media overheated while out of the tank?

Differential guide for why are my fish sick after biological filter media overheated while out of the tank?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after biological filter media froze during storage or transport?

Differential guide for why are my fish sick after biological filter media froze during storage or transport?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after freshwater biological media was exposed to strong salt water?

Differential guide for why are my fish sick after freshwater biological media was exposed to strong salt water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after regenerated filter resin was returned without complete neutralisation?

Differential guide for why are my fish sick after regenerated filter resin was returned without complete neutralisation?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a filter sock or pad was washed with fabric softener?

Differential guide for why are my fish sick after a filter sock or pad was washed with fabric softener?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a phosphate-remover media bag burst in the aquarium?

Differential guide for why are my fish sick after a phosphate-remover media bag burst in the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a zeolite media bag burst in the aquarium?

Differential guide for why are my fish sick after a zeolite media bag burst in the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after ceramic biological media produced a large dust cloud?

Differential guide for why are my fish sick after ceramic biological media produced a large dust cloud?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a pressurised CO2 cylinder reached an end-of-tank dump?

Differential guide for why are my fish sick after a pressurised co2 cylinder reached an end-of-tank dump?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after the CO2 cylinder was changed and the regulator was reset incorrectly?

Differential guide for why are my fish sick after the co2 cylinder was changed and the regulator was reset incorrectly?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after CO2 drop-checker reagent spilled into the aquarium?

Differential guide for why are my fish sick after co2 drop-checker reagent spilled into the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a pH controller or probe was calibrated incorrectly?

Differential guide for why are my fish sick after a ph controller or probe was calibrated incorrectly?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a dosing line siphoned continuously into the aquarium?

Differential guide for why are my fish sick after a dosing line siphoned continuously into the aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a dosing-pump airlock cleared and delivered an unintended catch-up dose?

Differential guide for why are my fish sick after a dosing-pump airlock cleared and delivered an unintended catch-up dose?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after slow-release fertiliser granules escaped from the substrate into the water?

Differential guide for why are my fish sick after slow-release fertiliser granules escaped from the substrate into the water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a soil or dirt substrate cap broke and exposed the underlying soil?

Differential guide for why are my fish sick after a soil or dirt substrate cap broke and exposed the underlying soil?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after active aquasoil was added to an established aquarium?

Differential guide for why are my fish sick after active aquasoil was added to an established aquarium?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after an anaerobic substrate pocket was opened during maintenance?

Differential guide for why are my fish sick after an anaerobic substrate pocket was opened during maintenance?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after RO product and reject lines were accidentally swapped?

Differential guide for why are my fish sick after ro product and reject lines were accidentally swapped?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after an exhausted carbon block allowed chlorine or chloramine breakthrough?

Differential guide for why are my fish sick after an exhausted carbon block allowed chlorine or chloramine breakthrough?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after an RO remineralisation cartridge became exhausted?

Differential guide for why are my fish sick after an ro remineralisation cartridge became exhausted?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after the water utility carried out emergency or shock chlorination?

Differential guide for why are my fish sick after the water utility carried out emergency or shock chlorination?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a well or bore pump was disinfected or serviced before aquarium water was drawn?

Differential guide for why are my fish sick after a well or bore pump was disinfected or serviced before aquarium water was drawn?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a bore or well pump replacement stirred sediment into the source water?

Differential guide for why are my fish sick after a bore or well pump replacement stirred sediment into the source water?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after water was stored in an IBC tote or drum with an unknown previous use?

Differential guide for why are my fish sick after water was stored in an ibc tote or drum with an unknown previous use?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a new water-storage barrel had a strong plastic or chemical odour?

Differential guide for why are my fish sick after a new water-storage barrel had a strong plastic or chemical odour?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after acrylic solvent cement was used on aquarium equipment or a sump?

Differential guide for why are my fish sick after acrylic solvent cement was used on aquarium equipment or a sump?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after thread-locking compound was used on aquarium plumbing?

Differential guide for why are my fish sick after thread-locking compound was used on aquarium plumbing?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after pipe dope or liquid thread sealant was used on wet-side aquarium plumbing?

Differential guide for why are my fish sick after pipe dope or liquid thread sealant was used on wet-side aquarium plumbing?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after petroleum jelly was used on an aquarium O-ring or seal?

Differential guide for why are my fish sick after petroleum jelly was used on an aquarium o-ring or seal?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after new vinyl tubing had a strong plastic or solvent odour?

Differential guide for why are my fish sick after new vinyl tubing had a strong plastic or solvent odour?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a chiller heat exchanger or coil showed corrosion?

Differential guide for why are my fish sick after a chiller heat exchanger or coil showed corrosion?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after a UV steriliser quartz sleeve cracked or broke?

Differential guide for why are my fish sick after a uv steriliser quartz sleeve cracked or broke?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after the activated-carbon postfilter on an ozone system became exhausted?

Differential guide for why are my fish sick after the activated-carbon postfilter on an ozone system became exhausted?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why are my fish sick after an ORP controller probe failed while ozone was in use?

Differential guide for why are my fish sick after an orp controller probe failed while ozone was in use?, with environmental checks, exposure clues, look-alikes and evidence-led next steps.

Why does my fish have a persistent slow-growing skin lump?

Differential guide for why does my fish have a persistent slow-growing skin lump?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a rapidly enlarging skin mass?

Differential guide for why does my fish have a rapidly enlarging skin mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have an ulcerated skin mass?

Differential guide for why does my fish have an ulcerated skin mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a skin mass that keeps bleeding?

Differential guide for why does my fish have a skin mass that keeps bleeding?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a black or dark pigmented mass?

Differential guide for why does my fish have a black or dark pigmented mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a yellow or orange pigmented mass?

Differential guide for why does my fish have a yellow or orange pigmented mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a reflective silver or blue mass?

Differential guide for why does my fish have a reflective silver or blue mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a hard fixed mass on a fin?

Differential guide for why does my fish have a hard fixed mass on a fin?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a soft fleshy mass on a fin?

Differential guide for why does my fish have a soft fleshy mass on a fin?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a persistent mass at the base of a fin?

Differential guide for why does my fish have a persistent mass at the base of a fin?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a firm mass on the gill cover?

Differential guide for why does my fish have a firm mass on the gill cover?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass visible inside the gill chamber?

Differential guide for why does my fish have a mass visible inside the gill chamber?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a persistent mass at the corner of the mouth?

Differential guide for why does my fish have a persistent mass at the corner of the mouth?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a growth inside the mouth?

Differential guide for why does my fish have a growth inside the mouth?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a firm mass beneath the lower jaw?

Differential guide for why does my fish have a firm mass beneath the lower jaw?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a persistent mass on top of the head?

Differential guide for why does my fish have a persistent mass on top of the head?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass behind the eye?

Differential guide for why does my fish have a mass behind the eye?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have an eye displaced by an orbital mass?

Differential guide for why does my fish have an eye displaced by an orbital mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a visible mass inside the eye?

Differential guide for why does my fish have a visible mass inside the eye?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a growth covering part of the pupil?

Differential guide for why does my fish have a growth covering part of the pupil?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass in the nasal opening or olfactory pit?

Differential guide for why does my fish have a mass in the nasal opening or olfactory pit?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a firm one-sided facial mass?

Differential guide for why does my fish have a firm one-sided facial mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a persistent mass along one side of the body?

Differential guide for why does my fish have a persistent mass along one side of the body?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a persistent mass at the tail base?

Differential guide for why does my fish have a persistent mass at the tail base?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a firm dorsal-body mass over the spine?

Differential guide for why does my fish have a firm dorsal-body mass over the spine?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a persistent mass in the abdominal body wall?

Differential guide for why does my fish have a persistent mass in the abdominal body wall?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a one-sided firm abdominal mass?

Differential guide for why does my fish have a one-sided firm abdominal mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have an internal mass visible through the abdomen?

Differential guide for why does my fish have an internal mass visible through the abdomen?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a persistent mass near the vent or cloaca?

Differential guide for why does my fish have a persistent mass near the vent or cloaca?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have persistent gonadal-region enlargement in a mature fish?

Differential guide for why does my fish have persistent gonadal-region enlargement in a mature fish?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a hard bony mass on the jaw?

Differential guide for why does my fish have a hard bony mass on the jaw?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a hard bony mass on a fin ray?

Differential guide for why does my fish have a hard bony mass on a fin ray?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have multiple persistent skin nodules?

Differential guide for why does my fish have multiple persistent skin nodules?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a single smooth persistent skin nodule?

Differential guide for why does my fish have a single smooth persistent skin nodule?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a flat plaque-like skin mass?

Differential guide for why does my fish have a flat plaque-like skin mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a stalked or pedunculated skin growth?

Differential guide for why does my fish have a stalked or pedunculated skin growth?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass that regrows after trauma or partial removal?

Differential guide for why does my fish have a mass that regrows after trauma or partial removal?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass with changing pigmentation?

Differential guide for why does my fish have a mass with changing pigmentation?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass that is interfering with swimming?

Differential guide for why does my fish have a mass that is interfering with swimming?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have an oral mass that prevents the mouth closing fully?

Differential guide for why does my fish have an oral mass that prevents the mouth closing fully?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a branchial mass with reduced movement of one gill cover?

Differential guide for why does my fish have a branchial mass with reduced movement of one gill cover?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a persistent mass with progressive weight loss?

Differential guide for why does my fish have a persistent mass with progressive weight loss?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass with normal appetite but ongoing body wasting?

Differential guide for why does my fish have a mass with normal appetite but ongoing body wasting?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have an abdominal mass with new buoyancy problems?

Differential guide for why does my fish have an abdominal mass with new buoyancy problems?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass with persistent bulging of one eye?

Differential guide for why does my fish have a mass with persistent bulging of one eye?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a skin mass that lifts or displaces the scales?

Differential guide for why does my fish have a skin mass that lifts or displaces the scales?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass arising from the edge of the operculum?

Differential guide for why does my fish have a mass arising from the edge of the operculum?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass at the base of the dorsal fin?

Differential guide for why does my fish have a mass at the base of the dorsal fin?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have a mass at the pectoral girdle or shoulder?

Differential guide for why does my fish have a mass at the pectoral girdle or shoulder?, with location, progression, look-alikes and evidence-led diagnostic next steps.

Why does my fish have slowly progressive body asymmetry caused by a focal mass?

Differential guide for why does my fish have slowly progressive body asymmetry caused by a focal mass?, with location, progression, look-alikes and evidence-led diagnostic next steps.

What can cause spawning frequency that suddenly becomes much higher than the pair’s normal pattern?

Breeding and reproductive differential for what can cause spawning frequency that suddenly becomes much higher than the pair’s normal pattern?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a mature female that becomes swollen but releases no eggs?

Breeding and reproductive differential for what can cause a mature female that becomes swollen but releases no eggs?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a fish that repeatedly goes through spawning behaviour without eggs being released?

Breeding and reproductive differential for what can cause a fish that repeatedly goes through spawning behaviour without eggs being released?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a female that looks in breeding condition but stops spawning?

Breeding and reproductive differential for what can cause a female that looks in breeding condition but stops spawning?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a mature male that stops producing visible milt during breeding attempts?

Breeding and reproductive differential for what can cause a mature male that stops producing visible milt during breeding attempts?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause spawning behaviour without any eggs or milt being released?

Breeding and reproductive differential for what can cause spawning behaviour without any eggs or milt being released?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause suspected eggs retained after a spawning attempt?

Breeding and reproductive differential for what can cause suspected eggs retained after a spawning attempt?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a swollen vent before spawning?

Breeding and reproductive differential for what can cause a swollen vent before spawning?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause spawning cycles that become irregular after previously being predictable?

Breeding and reproductive differential for what can cause spawning cycles that become irregular after previously being predictable?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a red or irritated vent during breeding?

Breeding and reproductive differential for what can cause a red or irritated vent during breeding?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause eggs being released before normal courtship is completed?

Breeding and reproductive differential for what can cause eggs being released before normal courtship is completed?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause repeated egg scattering with no apparent fertilisation?

Breeding and reproductive differential for what can cause repeated egg scattering with no apparent fertilisation?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a clutch containing many unusually small or underdeveloped eggs?

Breeding and reproductive differential for what can cause a clutch containing many unusually small or underdeveloped eggs?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause eggs that are released but collapse or deteriorate quickly?

Breeding and reproductive differential for what can cause eggs that are released but collapse or deteriorate quickly?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause an unusually small clutch compared with previous spawns?

Breeding and reproductive differential for what can cause an unusually small clutch compared with previous spawns?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause clutch size that keeps declining over successive spawns?

Breeding and reproductive differential for what can cause clutch size that keeps declining over successive spawns?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a female that progressively loses body condition during repeated spawning cycles?

Breeding and reproductive differential for what can cause a female that progressively loses body condition during repeated spawning cycles?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a female that refuses food before an expected spawning event?

Breeding and reproductive differential for what can cause a female that refuses food before an expected spawning event?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a breeding female taking progressively longer to recover after each spawn?

Breeding and reproductive differential for what can cause a breeding female taking progressively longer to recover after each spawn?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause one-sided abdominal swelling in a mature female?

Breeding and reproductive differential for what can cause one-sided abdominal swelling in a mature female?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a firm abdominal swelling in the ovarian region?

Breeding and reproductive differential for what can cause a firm abdominal swelling in the ovarian region?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a soft abdominal swelling in the ovarian region?

Breeding and reproductive differential for what can cause a soft abdominal swelling in the ovarian region?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause female breeding condition that persists much longer than the pair’s usual cycle?

Breeding and reproductive differential for what can cause female breeding condition that persists much longer than the pair’s usual cycle?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause an unexpectedly enlarged abdomen in a mature male?

Breeding and reproductive differential for what can cause an unexpectedly enlarged abdomen in a mature male?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause an enlarged male vent with no milt released?

Breeding and reproductive differential for what can cause an enlarged male vent with no milt released?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a fish developing mixed male and female sex characteristics?

Breeding and reproductive differential for what can cause a fish developing mixed male and female sex characteristics?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a mature male developing female-like body or gonadal characteristics?

Breeding and reproductive differential for what can cause a mature male developing female-like body or gonadal characteristics?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a mature female developing male-like secondary sex traits?

Breeding and reproductive differential for what can cause a mature female developing male-like secondary sex traits?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause normal breeding colour changes followed by repeated spawning failure?

Breeding and reproductive differential for what can cause normal breeding colour changes followed by repeated spawning failure?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause repeated courtship without the pair completing a spawn?

Breeding and reproductive differential for what can cause repeated courtship without the pair completing a spawn?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a mature fish that never develops expected breeding condition?

Breeding and reproductive differential for what can cause a mature fish that never develops expected breeding condition?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause spawning that stops after a change in source water?

Breeding and reproductive differential for what can cause spawning that stops after a change in source water?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause spawning that stops after a medication course?

Breeding and reproductive differential for what can cause spawning that stops after a medication course?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause spawning that stops after fish are moved to a new tank?

Breeding and reproductive differential for what can cause spawning that stops after fish are moved to a new tank?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause spawning that stops after a significant temperature change?

Breeding and reproductive differential for what can cause spawning that stops after a significant temperature change?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause spawning that stops after a major diet change?

Breeding and reproductive differential for what can cause spawning that stops after a major diet change?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause persistent infertility despite apparently normal spawning behaviour?

Breeding and reproductive differential for what can cause persistent infertility despite apparently normal spawning behaviour?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a persistently low fertilisation rate in otherwise normal-looking eggs?

Breeding and reproductive differential for what can cause a persistently low fertilisation rate in otherwise normal-looking eggs?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause apparently normal fertilisation followed by a persistently low hatch rate?

Breeding and reproductive differential for what can cause apparently normal fertilisation followed by a persistently low hatch rate?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause an unusually high rate of malformed embryos or hatchlings?

Breeding and reproductive differential for what can cause an unusually high rate of malformed embryos or hatchlings?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause fry output that falls despite apparently normal spawning?

Breeding and reproductive differential for what can cause fry output that falls despite apparently normal spawning?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a female whose abdomen shrinks without an observed spawning event?

Breeding and reproductive differential for what can cause a female whose abdomen shrinks without an observed spawning event?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause an irregular abdominal outline in a mature female?

Breeding and reproductive differential for what can cause an irregular abdominal outline in a mature female?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause the interval between successful spawns becoming progressively longer?

Breeding and reproductive differential for what can cause the interval between successful spawns becoming progressively longer?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a previously reliable breeding pair repeatedly skipping expected spawning cycles?

Breeding and reproductive differential for what can cause a previously reliable breeding pair repeatedly skipping expected spawning cycles?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause eggs being released in several unusually small batches instead of the pair’s normal spawning pattern?

Breeding and reproductive differential for what can cause eggs being released in several unusually small batches instead of the pair’s normal spawning pattern?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a female that appears gravid then loses swelling without an observed spawn?

Breeding and reproductive differential for what can cause a female that appears gravid then loses swelling without an observed spawn?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a mature pair that spawns repeatedly but never produces viable fry?

Breeding and reproductive differential for what can cause a mature pair that spawns repeatedly but never produces viable fry?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause normal male breeding behaviour while eggs remain consistently unfertilised?

Breeding and reproductive differential for what can cause normal male breeding behaviour while eggs remain consistently unfertilised?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause normal female breeding behaviour but consistently poor egg viability?

Breeding and reproductive differential for what can cause normal female breeding behaviour but consistently poor egg viability?, with husbandry checks, look-alikes and diagnostic next steps.

What can cause a pale liver seen during a fish necropsy?

Post-mortem differential for what can cause a pale liver seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause an unusually dark liver seen during a fish necropsy?

Post-mortem differential for what can cause an unusually dark liver seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a yellow or tan liver seen during a fish necropsy?

Post-mortem differential for what can cause a yellow or tan liver seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a mottled or patchy liver seen during a fish necropsy?

Post-mortem differential for what can cause a mottled or patchy liver seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause an enlarged liver seen during a fish necropsy?

Post-mortem differential for what can cause an enlarged liver seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause an unusually small liver seen during a fish necropsy?

Post-mortem differential for what can cause an unusually small liver seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a firm liver seen during a fish necropsy?

Post-mortem differential for what can cause a firm liver seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a fragile or friable liver seen during a fish necropsy?

Post-mortem differential for what can cause a fragile or friable liver seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause white spots or pale foci in the liver at necropsy?

Post-mortem differential for what can cause white spots or pale foci in the liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause red foci or haemorrhagic-looking areas in the liver at necropsy?

Post-mortem differential for what can cause red foci or haemorrhagic-looking areas in the liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause one or more liver nodules seen at necropsy?

Post-mortem differential for what can cause one or more liver nodules seen at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a cyst-like or fluid-filled space in the liver at necropsy?

Post-mortem differential for what can cause a cyst-like or fluid-filled space in the liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a gritty or mineral-like focus in the liver at necropsy?

Post-mortem differential for what can cause a gritty or mineral-like focus in the liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause prominent or thickened bile-duct-like structures in the liver at necropsy?

Post-mortem differential for what can cause prominent or thickened bile-duct-like structures in the liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause green bile-like staining around the liver at necropsy?

Post-mortem differential for what can cause green bile-like staining around the liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a liver that appears stuck or adhered to nearby organs at necropsy?

Post-mortem differential for what can cause a liver that appears stuck or adhered to nearby organs at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a rough or irregular liver surface at necropsy?

Post-mortem differential for what can cause a rough or irregular liver surface at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a pale vacuolated or foamy-looking liver at necropsy?

Post-mortem differential for what can cause a pale vacuolated or foamy-looking liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a single pale focus in the liver at necropsy?

Post-mortem differential for what can cause a single pale focus in the liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause multiple pale foci in the liver at necropsy?

Post-mortem differential for what can cause multiple pale foci in the liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a congested or blood-filled liver at necropsy?

Post-mortem differential for what can cause a congested or blood-filled liver at necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause liver tissue that breaks apart unusually easily during necropsy?

Post-mortem differential for what can cause liver tissue that breaks apart unusually easily during necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause an abnormal-looking liver after sudden unexplained fish death?

Post-mortem differential for what can cause an abnormal-looking liver after sudden unexplained fish death?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause similar liver abnormalities in several fish from the same aquarium?

Post-mortem differential for what can cause similar liver abnormalities in several fish from the same aquarium?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a normal-looking liver despite severe illness before death?

Post-mortem differential for what can cause a normal-looking liver despite severe illness before death?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause an enlarged kidney seen during a fish necropsy?

Post-mortem differential for what can cause an enlarged kidney seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a pale kidney seen during a fish necropsy?

Post-mortem differential for what can cause a pale kidney seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause an unusually dark kidney seen during a fish necropsy?

Post-mortem differential for what can cause an unusually dark kidney seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a swollen kidney seen during a fish necropsy?

Post-mortem differential for what can cause a swollen kidney seen during a fish necropsy?, with autolysis limits, water/exposure checks and diagnostic next steps.

What can cause a small or shrunken kidney seen during a fish necropsy?