Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Epalzeorhynchos bicolor

Red tailed black shark

Red tailed black shark, Epalzeorhynchos bicolorRed tailed black shark, Epalzeorhynchos bicolor
Photos by Andy Rapson


Epalzeorhynchos: Greek, epalzes, -es, -es = curative + Greek, rhyngchos = snout.

General Notes:

Red tailed black sharks are stunning fish and make an outstanding centrepiece fish to a small community tank but they are quite grumpy. Only one can be kept in a tank and similar looking fish like flying foxes are best avoided because red tailed black sharks are very territorial particularly with their own kind and other similar looking fish. They will also give chase to other species which get to close but no harm is done other than the chase. If tank mates are well chosen there is no need to be put off keeping one of these fish. In a large enough tank the fish behaves far better and spends its time grazing on algae and diatoms, The one pictured above is my own red tailed black shark and I never witnessed it take any commercial food, it seemed to fined all the food it required in the tank itself and didn't seem to need any supplementary feeding from me. All red tailed black sharks offered for sale have been bred in captivity.


Commercial food may be taken if the fish can't find enough algae or diatoms in the aquarium, feeding presents no problems but don't be to surprised if the fish appears to ignore all food offered, as long as it remains plump it is fine.


It is extremely difficult to tell the sexes apart and there is no reliable method. Some say that the females are heavier bodied than the males but at best this is just a guide.


Red tailed black sharks have never been bred without the use of hormones, there are no reports of hobbyists breeding this species.

Wild status

For a long time it was thought that Epalzeorhynchos bicolor was extinct in the wild but some fish have been discovered living wild, Epalzeorhynchos bicolor is still considered to be critically endangered and facing threats from agricultural pollution. Loss of habitat is thought to be the reason for the decline of wild stocks rather than over collecting by the aquarium trade.

Information at a glance

pH: 6.5 - 7.5
dGH: 5 - 15
Temperature: 22 - 26°C (72 - 78°F)
Diet: Omnivore
Size: 12cm (4.8in)
Min tank size: 225 litres
Difficulty level: Intermediate
Aquarium type: Community
Swimming level: Lower

Distribution and habitat

distribution map for Red tailed black shark, Epalzeorhynchos bicolor

Origin: Asia: Chao Phraya basin, Thailand. Reported from the Mekong basin

Habitat: Inhabits mainstream rivers and floodplains


Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Epalzeorhynchos
Species: E. bicolor (Smith, 1931)

Common name:
Red tailed black shark

Synonyms: Labeo bicolor