All fish / Cetopsidae

Blue Whale Catfish

Cetopsis coecutiens

Also known as whale catfish, blue whale catfish, candiru azul, bluish whale catfish, cetopsis catfish, ブルーホエールキャット, 蓝鲸鲶

A smooth, scaleless catfish with a bluish-grey back, pale belly, tiny eyes and a rounded snout, giving it a small whale-like look. It is kept by specialist catfish keepers for its unusual appearance and fast, restless swimming.

Care at a glance

Care level

Hard

Temperament

Aggressive

Adult size

25 cm

Temperature

23 to 28 °C

pH

6 to 7.5

Smallest tank

750 litres

Keep as

Best kept alone or in a large species-only group

Diet

Carnivore: meaty foods such as fish fillet, prawn, mussel and earthworms

Swims

Middle of the tank

Lifespan

10 years or more

Water

Freshwater

Wild range

Amazon and Tocantins basins in Brazil, Peru, Colombia and Ecuador

Breeding

Not known to have been bred in aquariums. Little is recorded about its spawning in the wild.

Good to know

A powerful scavenger and predator that bites chunks from other fish and can eat anything it can swallow, so tankmates must be large and robust or absent. Needs a very large, well-oxygenated tank with strong flow and secure cover.