TankBud

Red-tailed black shark

Epalzeorhynchos bicolor

FreshwaterFish

Red-tailed black shark (Epalzeorhynchos bicolor)
Astellar87 · CC BY-SA 4.0

Care at a glance

Temperature
68–79°F
20–26°C
pH
6.5–7.5
Adult size
4.7 in
12 cm
Minimum tank
63 gal
240 L
Temperament
Mostly peaceful
Social behavior
Solitary
Own kind
One per tank
Tankmates
With caution
Swim level
Bottom
Diet
Omnivore
Difficulty
Medium
Breeding
Egg layer
Rarity
Common
Family
Cyprinidae
Origin
Thailand

Overview

The red-tailed black shark is a solitary, territorial bottom fish for a larger community tank. It is a step up from the easiest fish.

Did you know

The red-tailed black shark was once common in Thai rivers, then feared extinct in the wild for years before small populations turned up again. The hobby's supply comes almost entirely from farms, mostly in Southeast Asia. It is a rare case of aquaculture keeping a species available while its native range stays in trouble.

Caring for the red-tailed black shark

Keep just one red-tailed black shark per tank, in 63 gal (240 L) or larger. It holds the bottom and claims territory, so break up the tank with plenty of caves, wood and hiding spots.

Keep the water at 68 to 79°F (20 to 26°C) with a pH of 6.5 to 7.5. Steady flow and good oxygen keep it comfortable. Feed sinking pellets and algae wafers, with the occasional frozen treat such as bloodworms or brine shrimp.

The red-tailed black shark is solitary, territorial and only mostly peaceful, so choose its tank mates with care. It chases off its own kind and anything that looks similar. It does best in a larger community with active fish that swim in the middle and upper water, out of its zone. It is an egg-layer that rarely breeds in home tanks.

Good to know

The red-tailed black shark is a member of the carp family, Cyprinidae, with a jet-black body and a bright red tail. The IUCN lists it as Critically Endangered in the wild because of habitat loss.

In the wild

Red-tailed black sharks come from the Chao Phraya basin in Thailand. They live in clear, flowing rivers and streams over rock and sand, with plants and roots for shelter.

Common questions

What size tank does a red-tailed black shark need?

A red-tailed black shark needs at least 63 gal (240 L). It spends most of its time in the bottom.

What temperature and pH does a red-tailed black shark need?

A red-tailed black shark is comfortable at 68–79°F (20–26°C) with a pH of 6.5–7.5.

What does a red-tailed black shark eat?

A red-tailed black shark eats sinking pellets and algae wafers. Give it the occasional frozen treat as well, such as bloodworms or brine shrimp.

How big does a red-tailed black shark get?

An adult red-tailed black shark reaches about 4.7 in (12 cm).

How does a red-tailed black shark breed?

Red-tailed black sharks lay eggs, but they rarely breed in home tanks.

Related species