Betta Trading


Redtail Black Shark

An Aquarium Fish Extinct in the Wild

The "Redtail Black Shark", "Epalzeorhynchos bicolour", is also called "The Red Tail Shark", "Redtail Shark Minnow", "Red-tailed labeo", "Redtailed Shark", "Red-Tailed Black Sharkminnow," and the "Fire Tail". The scientific name used to be Labeo bicolour. The genus is sometimes misspelled Epalzeorhynchus.


It is not a true shark, being more closely related to the loaches and barbs.  This fish was native to Thailand, being found in the river basin of the Chao Phraya.  It was in the streams and wetlands of this river area.  There were also reports of it in the Mekong.


The Redtail Black Shark can grow to about 7 inches (18 cm) long and can live for up to about 15 years.


The Redtail Black Shark is probably extinct in the wild.  It is uncertain why it became extinct.  Although collecting of wild fish for the aquarium trade has been suspected, it appears more likely that changes in its habitat are the real cause.


The Redtail Black Sharks available now are captive bred fish, being mainly produced in ponds in Thailand.

Water Conditions

The Redtail Black Shark prefers reasonably soft water, but will adapt to neutral water with a moderate hardness.  This is a tropical fish and a temperature of between 22 and 26 degrees C (72-78 degrees F) is ideal although the fish will survive for a while in higher temperatures.


This is a big fish, so it needs a big tank.  Although they can certainly be kept in a 3 foot (90 cm) long tank, a bigger one than this is recommended.  Plenty of hiding places made of such things as rocks or drift wood should be provided as well as plants.


The Redtail Black Shark is an omnivore, eating plant material as well as animal food.  Its mouth is on the lower part of its head so they are more adapted to eating pellets or wafer type fish food on the bottom than flakes on the water surface.


The Redtail Black Shark is territorial.  This means that in most cases you are better to have only one of this species in your aquarium.  If you have two, they will squabble and eventually the dominant fish will probably end up killing the weaker one.


In aquarium shops (including ours) you will often see quite a lot of small Redtail Black Sharks together; living in apparent harmony.  While they are small, they will tolerate the presence of reasonable numbers of their own kind for a while. However, if the number drops to less than 4, one fish will become dominant.  This antipathy to their own kind also applies to related fish of similar appearance.


They will tolerate different types of fish better, but you should choose ones that are vigorous and not too small, so avoid the smallest of the tetras, barbs and Rasboras.  The larger tetras, barbs and Rasboras are better.

Disease Susceptibility

The Redtail Black Shark, like its relative the Clown Loach, is quite vulnerable to white spot, or Ich, caused by the parasite Ichthyophthirius multifilis.  This is readily curable as long as it is caught early on.  Use one of the dye type treatments at the half rate.


The Redtail Black Shark is very rarely bred in aquariums.  The fish sold commercially are generally bred in ponds, often with the aid on hormones.

Sources, and,