AquaNexus verified profile
Wrestling halfbeak
Dermogenys pusilla
A surface-dwelling livebearing halfbeak requiring a long covered aquarium, a female-biased group and careful verification against similar Dermogenys.
Outcome: PASSED Permanent ID: 735
Profile overview
- Scientific Name
- Dermogenys pusilla
- Identity and search names
- Silver halfbeak, Dermogenys pusilla
- Category
- Freshwater fish
- Subgroup
- Livebearers
- Environment
- Freshwater aquarium
- Origin
- Southeast Asia
- Care
- Intermediate
- Adult Size
- 5–7 cm
- Lifespan
- 2–5 years
- Tank
- At least 90 L in a long, tightly covered aquarium for eight or more
- Temp
- 22–28 °C
- pH
- 7.0–8.2
- Hardness
- Moderate to hard
- Salinity
- Freshwater; no routine salt addition
- Lighting
- Normal aquarium lighting
- Placement
- Surface
- Diet
- Surface-feeding omnivore focused on small insects, crustaceans and suitably sized floating 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. The trade label can include other Dermogenys, including D. sumatrana. Verify scientific identity, protect the elongated lower jaw and seal every lid gap.
- 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. CURRENT
App-ready care, welfare and biosecurity details
Identity Scope
Single-species profile for Dermogenys pusilla. Preserve permanent AquaNexus ID 735, slug wrestling-halfbeak and route /species/wrestling-halfbeak/; retain former combinations, locality labels and trade names only as searchable aliases.
Adult Size And Space
Expected adult size: 5–7 cm. Minimum permanent housing: At least 90 L in a long, tightly covered aquarium for eight or more. Plan around adult dimensions, activity, social structure, aggression, oxygen demand and waste production rather than sale size.
Social Structure
Keep a female-biased group of at least eight with dense surface cover; males may wrestle and injure one another in cramped quarters
Swimming Zone
Primary zone: Surface. Keep that zone usable for movement, feeding, refuge and escape.
Feeding Ecology
Surface-feeding omnivore focused on small insects, crustaceans and suitably sized floating foods
Feeding Plan
Offer small floating live, frozen and prepared foods once or twice daily; prevent food from sinking before surface fish feed
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
Long, tightly covered aquarium with calm surface zones, floating plants, open feeding lanes and no sharp obstacles near the surface
Compatibility Plan
Choose calm tankmates that do not rush the surface or nip elongated jaws; avoid crowding and aggressive male ratios
Breeding Plan
Internal livebearer; females release developed free-swimming fry Parental care: No post-birth parental care; adults may eat fry, so provide dense floating cover or move late-stage females carefully.
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 trade label can include other Dermogenys, including D. sumatrana. Verify scientific identity, protect the elongated lower jaw and seal every lid gap.
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 trade label can include other Dermogenys, including D. sumatrana. Verify scientific identity, protect the elongated lower jaw and seal every lid gap.
Adult Projected Load
Plan filtration and stocking for the full adult size (5–7 cm), the complete social group and peak feeding waste, not the current shop size. Permanent housing remains At least 90 L in a long, tightly covered aquarium for eight or more.
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 are decision support, not permission to ignore welfare limits. Override only with specimen-specific evidence, equivalent risk controls and a recorded reason; never override legal, biosecurity, provenance or no-release requirements.
Sources and review basis
- Eschmeyer’s Catalog of Fishes — Dermogenys pusilla: Taxonomy — accepted name, former combinations, synonyms and identity cross-check
- ITIS — Dermogenys pusilla: Taxonomy and identity — valid species and corrected feminine spelling
- IUCN Red List search — Dermogenys pusilla: 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.