- Common name
- Amazon puffer
- Scientific name
- Sphoeroides asellus
- Category
- Freshwater fish
- Group
- Pufferfishes
- Environment
- Primarily freshwater aquarium; some natural populations occur in brackish or marine-influenced habitats
- Origin
- Western Atlantic drainages from Colombia south to Pará, Brazil, including the Amazon system upstream to Peru
- Care level
- Advanced
- Adult size
- Up to 12.8 cm standard length
- Expected lifespan
- Plan for 8–12 years; strong teeth, specialist feeding and individual aggression make this a long-term advanced-care fish.
- Minimum housing
- At least 200 L for one or a carefully monitored compatible group, with powerful filtration, open movement space and visual barriers
- Temperature
- 22–28 °C
- pH
- 5.5–7.2
- Hardness / minerals
- 5–15 °dGH (about 89–268 mg/L as CaCO3)
- Salinity
- Primarily freshwater; can tolerate brackish water but routine salt is not required for freshwater stock
- Lighting
- Normal with shaded structured areas
- Placement / zone
- Active throughout the aquarium.
- Filtration
- Use mature biological filtration sized for the complete adult amazon puffer group, with guarded intakes and accessible mechanical capture. Keep flow moderate to strong with open movement lanes and calmer structured refuge where the fish lives, and maintain undetectable ammonia and nitrite.
- Aeration
- Maintain reliable surface agitation and oxygen exchange at all times. Increase aeration during warm weather, medication, transport recovery, heavy feeding or any sign of rapid breathing.
- Maintenance
- Perform regular matched-water changes guided by nitrate and waste, remove uneaten food and trapped detritus, clean mechanical media without disrupting the biofilter, and record feeding, body condition, respiration and aggression.
Identity and search names
Single-profile scope for Sphoeroides asellus. Preserve permanent AquaNexus ID 29, slug amazon-puffer and route /species/amazon-puffer/; retain former combinations, locality labels, domestic-form names and trade names only as searchable aliases.
Search names: Amazon puffer, Sphoeroides asellus, Colomesus asellus, South American puffer, Amazonian puffer
Environment and housing
Open swimming space, wood or rock barriers, smooth surfaces and accessible feeding areas.
Social structure: Can be social but individuals vary. Monitor nipping, food competition and persistent pursuit; separate incompatible fish.
Feeding and nutrition
Feeding ecology: Hard-shelled invertebrates and varied meaty foods; dental wear must be monitored individually
Feeding routine: One or two measured feeds daily; adapt to body condition and species ecology
Breeding, reproduction or spread
Dependable routine home-aquarium breeding remains unknown; do not promote anecdotal spawning claims as an established method
Detailed care and app-ready planning
- Identity scope
- Single-profile scope for Sphoeroides asellus. Preserve permanent AquaNexus ID 29, slug amazon-puffer and route /species/amazon-puffer/; retain former combinations, locality labels, domestic-form names and trade names only as searchable aliases.
- Adult size and space
- Expected adult size: Up to 12.8 cm standard length. Minimum permanent housing: At least 200 L for one or a carefully monitored compatible group, with powerful filtration, open movement space and visual barriers. Plan around adult dimensions, activity, social structure, aggression, oxygen demand and waste production rather than sale size.
- Social structure
- Can be social but individuals vary. Monitor nipping, food competition and persistent pursuit; separate incompatible fish.
- Swimming zone or placement
- Primary zone: Active throughout the aquarium.. Keep that zone usable for movement, feeding, refuge and escape.
- Feeding ecology
- Hard-shelled invertebrates and varied meaty foods; dental wear must be monitored individually
- Feeding plan
- One or two measured feeds daily; adapt to body condition and species ecology
- Water stability
- Maintain 22–28 °C; pH 5.5–7.2; hardness or minerals: 5–15 °dGH (about 89–268 mg/L as CaCO3); salinity: Primarily freshwater; can tolerate brackish water but routine salt is not required for freshwater stock. Stability, oxygenation and nitrogen-cycle control matter more than chasing one exact value.
- Habitat structure
- Open swimming space, wood or rock barriers, smooth surfaces and accessible feeding areas.
- Compatibility plan
- Species-focused housing is safest; may nip fins and attack invertebrates
- Breeding or reproduction plan
- Dependable routine home-aquarium breeding remains unknown; do not promote anecdotal spawning claims as an established method Parental care: Unknown for dependable aquarium planning.
- Quarantine
- Quarantine new livestock in a separate cycled system for at least 30 days. Observe appetite, respiration, waste, skin, fins and behaviour; use dedicated equipment and never add transport water to the established aquarium.
- Welfare checks
- Maintain the stated adult space and social structure, verify feeding, and intervene early when injury, exclusion, weight loss, abnormal respiration or altered behaviour appears. The accepted current combination is Sphoeroides asellus; Colomesus asellus remains an important former name. Strong teeth, possible toxin risk and individual aggression require specialist handling and no consumption.
- Biosecurity and release
- Never release fish, fry, eggs, aquarium water, sediment, plants or live foods into drains, dams or natural waterways. Confirm current Australian import conditions and South Australian possession, trade and movement rules before acquisition or transfer.
- Main risk
- The accepted current combination is Sphoeroides asellus; Colomesus asellus remains an important former name. Strong teeth, possible toxin risk and individual aggression require specialist handling and no consumption.
- Adult projected load
- Project biological load from the full adult amazon puffer group, adult body mass, feeding pattern, activity and social requirement rather than juvenile sale size. Hard-shelled meaty feeding creates a high solids and protein load, while dental management and aggression add ongoing husbandry burden.
- Filtration
- Use mature biological filtration sized for the complete adult amazon puffer group, with guarded intakes and accessible mechanical capture. Keep flow moderate to strong with open movement lanes and calmer structured refuge where the fish lives, and maintain undetectable ammonia and nitrite.
- Aeration
- Maintain reliable surface agitation and oxygen exchange at all times. Increase aeration during warm weather, medication, transport recovery, heavy feeding or any sign of rapid breathing.
- Maintenance
- Perform regular matched-water changes guided by nitrate and waste, remove uneaten food and trapped detritus, clean mechanical media without disrupting the biofilter, and record feeding, body condition, respiration and aggression.
- Overridable warnings
- Non-overridable: do not accept persistent ammonia or nitrite, oxygen distress, starvation, chronic aggression or inadequate adult space. Different equipment, stocking or maintenance methods may be used only when measured water quality and adult welfare remain equivalent or better. This is primarily a freshwater species under the accepted name Sphoeroides asellus; do not force routine marine salinity, consume the fish or handle it casually.
Compatibility, welfare and risk
Compatibility: Species-focused housing is safest; may nip fins and attack invertebrates
Welfare: Maintain the stated adult space and social structure, verify feeding, and intervene early when injury, exclusion, weight loss, abnormal respiration or altered behaviour appears. The accepted current combination is Sphoeroides asellus; Colomesus asellus remains an important former name. Strong teeth, possible toxin risk and individual aggression require specialist handling and no consumption.
Main warning: The accepted current combination is Sphoeroides asellus; Colomesus asellus remains an important former name. Strong teeth, possible toxin risk and individual aggression require specialist handling and no consumption.
Biosecurity and release
Never release fish, fry, eggs, aquarium water, sediment, plants or live foods into drains, dams or natural waterways. Confirm current Australian import conditions and South Australian possession, trade and movement rules before acquisition or transfer.