Red-tail Black Shark (Epalzeorhynchos bicolor) Care Guide
A stunning fish with a jet-black body contrasted by a vivid red tail. Highly territorial, especially towards other bottom-dwelling and similarly shaped fish. Only one should be kept per tank.
Compiled by Aquairi from published sources · Published · Updated
Overview
Epalzeorhynchos bicolor is a species in the family Cyprinidae. A stunning fish with a jet-black body contrasted by a vivid red tail. Highly territorial, especially towards other bottom-dwelling and similarly shaped fish. Only one should be kept per tank. Needs plenty of hiding places among driftwood and rocks.
Taxonomy
- Family: Cyprinidae
- Genus: Epalzeorhynchos
- Scientific name: Epalzeorhynchos bicolor
- Other names: Red-tailed Shark, Labeo bicolor
- Origin: Southeast Asia
Habitat
Epalzeorhynchos bicolor is a cyprinid "shark" from rivers and floodplains of Thailand in Southeast Asia, now critically endangered in the wild. It is a territorial bottom dweller that grazes algae and biofilm and defends a feeding area against similar fish.
Tank requirements
- Minimum tank volume: 200 L
- Temperature: 22-26 °C
- pH: 6.5-7.5
- GH: 5-15 °dGH
- Water flow: moderate
- Adult size: 10-12 cm
- Lifespan: 5-8 years
- Difficulty: intermediate
Diet
Classified as omnivore. Recommended feeding frequency: 2x daily. In captivity, offer a varied diet appropriate to the species — quality prepared foods supplemented with frozen or live items of suitable size.
Compatibility
- Temperament: aggressive
- Position in tank: bottom
- Compatible tank mates: Tiger Barb, Giant Danio, Clown Loach
- Avoid with: Rainbow Shark, Another Red-tail, Small Bottom Dwellers, Corydoras
Breeding
- Breeding strategy: egg-layer
- Breeding difficulty: advanced
Red-tail Black Shark Breeding Guide
Overview
Epalzeorhynchos bicolor is an egg-laying cyprinid that is listed as Critically Endangered on the IUCN Red List (2011). It was believed extinct in the wild between 1996 and 2011, with a single specimen rediscovered in 2013 along the Mae Khlong River in west Thailand. Virtually all aquarium fish are commercially produced.
Sexing
Sex is difficult to determine until the fish are roughly 15 months old. Females are larger and wider-bodied, while males show brighter coloration, slimmer bodies and a more pointed dorsal fin.
Spawning Behavior & Trigger
Spawning triggers, mating cues and natural behaviour remain poorly understood. The species is a confirmed egg-layer, but on commercial farms reproduction is induced by hormone injection rather than by recreating a natural spawning trigger, and no replicable aquarium spawning method exists for hobbyists.
Common Challenges
Extreme intraspecific aggression prevents keeping more than one individual per tank, removing any chance of natural pairing. Even where hormone-induced spawning succeeds, high post-spawning mortality is reported. The species' conservation status further means that ex-situ breeding is recommended at the program level rather than as a hobby pursuit.