All fish / Pangasiidae

Iridescent Shark

Pangasianodon hypophthalmus

Also known as iridescent shark catfish, siamese shark, sutchi catfish, striped catfish, swai, tra, albino iridescent shark, pangasius, iridescent catfish, ปลาสวาย, ikan patin, patin siam

Juveniles are sleek silver catfish with dark side stripes and a shimmering sheen, and they are sold cheaply as small active shoaling fish. Adults become plain grey and very large, so in practice it suits public aquaria, huge indoor ponds or fish farms rather than home tanks.

Care at a glance

Care level

Hard

Temperament

Peaceful

Adult size

100 cm

Temperature

22 to 28 °C

pH

6.5 to 7.5

Smallest tank

5000 litres

Keep as

Group of 3 or more in very large systems, or kept singly

Diet

Omnivore: pellets, fish and prawn pieces, vegetables and fruit

Swims

Middle of the tank

Lifespan

15 to 20 years

Water

Freshwater

Wild range

Mekong and Chao Phraya basins (Thailand, Laos, Cambodia, Vietnam)

Breeding

It migrates upstream to spawn in rivers and does not breed in home aquariums. It is bred in vast numbers on Asian farms using hormone injections.

Good to know

Grows to around 1 m or more and is nervous, often injuring itself by dashing into glass, so it outgrows almost every home aquarium. Wild stocks are listed as Endangered by the IUCN, though farmed fish are abundant.