AquaNexus verified profile
Swordtail
Xiphophorus hellerii
Swordtail is Xiphophorus hellerii, an active Central American livebearer needing a long covered aquarium, female-biased social planning and strict prevention of release or uncontrolled hybridisation.
Outcome: PASSED Permanent ID: 672
Profile overview
- Scientific Name
- Xiphophorus hellerii
- Identity and search names
- green swordtail, red swordtail
- Category
- Freshwater fish
- Subgroup
- Livebearers
- Environment
- Freshwater aquarium
- Origin
- Atlantic-slope rivers from Veracruz in Mexico through Belize, Guatemala and Honduras; introduced widely elsewhere
- Care
- Beginner to intermediate
- Adult Size
- Females commonly 10–12 cm; large males may reach about 14 cm including the sword
- Lifespan
- 2–5 years
- Tank
- At least 160 L for a female-biased group, with a long covered swimming area
- Temp
- 22–28 °C
- pH
- 7.0–8.2
- Hardness
- Moderate to hard
- Salinity
- Freshwater; no routine salt addition
- Lighting
- Normal aquarium lighting
- Placement
- Mid to upper water
- Diet
- Omnivore taking algae, plant material, small invertebrates and prepared foods
- Filtration
- Use mature biological filtration with effective mechanical solids capture and turnover matched to the species’ natural flow needs. Protect intakes, preserve established media during cleaning and keep ammonia and nitrite at zero.
- Aeration
- Maintain continuous surface agitation and dependable dissolved oxygen across the whole aquarium. Increase oxygen reserve in warm water, strong-current systems, dense groups, medication periods and power interruptions.
- Maintenance
- Observe feeding, respiration, body condition and social behaviour daily; test nitrogen waste and key chemistry on a schedule; clean mechanical media before trapped waste decomposes; and perform regular temperature- and chemistry-matched water changes.
- 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. Swordtails jump, males can harass females relentlessly, and aquarium strains may hybridise. Never release them: established non-native populations can affect native aquatic communities.
- Biosecurity
- 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.
- Review Status
- PASSED
- Source Status
- CURRENT — accepted identity or explicitly bounded species profile; husbandry, welfare, sources and Australian/South Australian biosecurity rechecked.
App-ready care, welfare and biosecurity details
Identity Scope
Single-species profile for Xiphophorus hellerii. Preserve permanent AquaNexus ID 672, slug swordtail and route /species/swordtail/; retain former combinations, locality labels and trade names only as searchable aliases.
Adult Size And Space
Expected adult size: Females commonly 10–12 cm; large males may reach about 14 cm including the sword. Minimum permanent housing: At least 160 L for a female-biased group, with a long covered swimming area. Plan around adult dimensions, activity, social structure, aggression, oxygen demand and waste production rather than sale size.
Social Structure
Keep one male with at least three females, or a managed single-sex group; multiple males need much more space and visual separation
Swimming Zone
Primary zone: Mid to upper water. Keep that zone usable for movement, feeding, refuge and escape.
Feeding Ecology
Omnivore taking algae, plant material, small invertebrates and prepared foods
Feeding Plan
Offer varied plant-rich prepared foods and small invertebrate foods once or twice daily; prevent dominant adults monopolising food
Water Stability
Maintain 22–28 °C; pH 7.0–8.2; hardness or minerals: Moderate to hard; salinity: Freshwater; no routine salt addition. Stable oxygenation and nitrogen-cycle control matter more than chasing one exact value.
Habitat Structure
A long covered tank with current, plant cover and room for males to avoid each other.
Compatibility Plan
Use active fish that share moderately hard alkaline water; avoid fin nippers, slow long-finned fish and uncontrolled hybridisation with other Xiphophorus
Breeding Plan
Internal livebearer; females can store sperm and produce repeated broods of free-swimming fry Parental care: No post-birth parental care; adults may eat fry.
Quarantine
Quarantine new fish in a separate cycled aquarium with dedicated equipment. Match temperature and mineral chemistry gradually, confirm feeding, respiration, skin, fins and waste, 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. Swordtails jump, males can harass females relentlessly, and aquarium strains may hybridise. Never release them: established non-native populations can affect native aquatic communities.
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
Swordtails jump, males can harass females relentlessly, and aquarium strains may hybridise. Never release them: established non-native populations can affect native aquatic communities.
Adult Projected Load
Plan filtration and stocking for the full adult size (Females commonly 10–12 cm; large males may reach about 14 cm including the sword), the complete social group and peak feeding waste, not the current shop size. Permanent housing remains At least 160 L for a female-biased group, with a long covered swimming area.
Filtration
Use mature biological filtration with effective mechanical solids capture and turnover matched to the species’ natural flow needs. Protect intakes, preserve established media during cleaning and keep ammonia and nitrite at zero.
Aeration
Maintain continuous surface agitation and dependable dissolved oxygen across the whole aquarium. Increase oxygen reserve in warm water, strong-current systems, dense groups, medication periods and power interruptions.
Maintenance
Observe feeding, respiration, body condition and social behaviour daily; test nitrogen waste and key chemistry on a schedule; clean mechanical media before trapped waste decomposes; and perform regular temperature- and chemistry-matched water changes.
Overridable Warnings
Warnings may be overridden only with documented specimen-specific evidence and equivalent risk controls. Adult housing, oxygen, compatibility, legal provenance, disease control and no-release requirements cannot be overridden.
Sources and review basis
- Eschmeyer’s Catalog of Fishes — Xiphophorus hellerii: Taxonomy — accepted name, former combinations, synonyms and identity cross-check
- USGS NAS — Green swordtail: Distribution and biosecurity — established non-native populations and aquarium-release pathway
- IUCN Red List search — Xiphophorus hellerii: Conservation and provenance — wild-status, locality and collection-risk cross-check
- PIRSA — South Australian noxious fish list: Australian biosecurity — current South Australian possession, trade and movement restrictions
- DAFF — importing live ornamental fish to Australia: Australian biosecurity — national live-fish import pathways and permitted-species warning
AquaNexus uses original editorial synthesis. Exact import, possession, movement and disposal requirements must be rechecked with the current authority before acquisition or transfer.