Species profile
Rainbow Shark
Epalzeorhynchos frenatum
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 benthic cyprinid; best kept singly in ordinary community tanks with strong structure and good water movement.
Water parameters
Suggested general range for long-term care.
Temperature
24–27 °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
1.8
Adults defend feeding and resting areas, especially against similarly shaped bottom fish. Do not confuse grazing behaviour with a guaranteed algae-control role.
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 frenatum
Alternative names
Rainbow Shark, Ruby Shark, Red-fin Shark
Native range
Mainland Southeast Asia, particularly Mekong and Chao Phraya drainage systems.
Natural habitat
Riverine fish associated with flowing water, hard surfaces, wood and grazing areas; seasonal movement occurs in nature.
Diet & feeding
Aufwuchs-grazing omnivore; provide algae/vegetable matter plus quality sinking foods and invertebrate protein.
Breeding & sexing
Research-backed guidance for identifying sexes and reproductive behaviour.
Sexing
Adult females are often deeper-bodied; reliable sexing of juveniles is difficult.
Breeding
Commercial stocks are commonly captive produced, but routine home-aquarium spawning is uncommon and should not be presented as easy.