Species profile
Redtail Black Shark
Epalzeorhynchos bicolor
Semi aggressive
Moderate care
200 L minimum aquarium
12–15 cm adult size
Bottom
Can be kept singly
About this species
General notes for hobby use.
Territorial bottom-dwelling cyprinid; keep singly in most home aquaria and avoid other similarly shaped territorial grazers.
Water parameters
Suggested general range for long-term care.
Temperature
22–27 °C
pH
6–7.5
GH
Up to 18 dGH
KH
Not yet documented
Flow preference
Moderate–high
Data confidence
Verified
Behaviour
General behaviour traits used by TanksConnected compatibility checks.
Minimum group size
Can be kept singly
Tank zone
Bottom
Territory level
High
Predation risk
None
Bioload factor
2
Adults may relentlessly chase similar bottom fish. Provide visual barriers, caves/wood and open swimming room.
Compatibility flags
Quick cautions for common tank-planning issues.
Fin nipper
No
Plant safe
Yes
Shrimp safe
No / caution
Snail safe
Yes
Cave breeder
No
Digs substrate
No
Jump risk
Yes
Natural history & care
Research-backed context for long-term aquarium care.
Lifespan
Not yet documented
Diet type
Omnivore
Minimum aquarium volume
200 L
Minimum footprint
120 × 45 cm
Accepted scientific name
Epalzeorhynchos bicolor
Alternative names
Red-tailed Black Shark, Redtail Shark
Native range
Thailand, historically associated with the Chao Phraya and Mae Klong river systems.
Natural habitat
Flowing riverine habitat with hard surfaces and cover; captive fish benefit from clean oxygenated water and structured territories.
Diet & feeding
Aufwuchs-grazing omnivore; feed vegetable matter, algae-based foods and varied sinking protein foods.
Breeding & sexing
Research-backed guidance for identifying sexes and reproductive behaviour.
Sexing
Mature females may be fuller-bodied; external sexing is otherwise unreliable.
Breeding
Most aquarium-trade fish are commercially bred; ordinary home-aquarium breeding remains uncommon.