Mekong Giant Catfish

Pangasianodon gigas is listed as Critically Endangered on the IUCN Red List, with wild populations critically depleted by overfishing and dam construction across its Mekong River range. Adults are enormous, reaching up to 3 metres and over 300 kg in the wild, though captive specimens grow more slowly. Unlike most large catfish, adults are almost entirely herbivorous, lacking functional teeth and feeding instead on algae and soft plant matter.

In aquaria, only very large public institutions can responsibly house adult specimens. Young fish can be maintained in 10 000+ litre systems with excellent filtration and regular large water changes. They are surprisingly peaceful given their size and will co-exist with other large, non-aggressive fish. The Mekong Giant Catfish is a powerful symbol of the conservation crisis facing freshwater megafauna.

Keeping this species carries significant ethical responsibility. Purchasers should ensure specimens are captive-bred from licensed breeding programmes, and long-term housing plans must be in place before acquisition. Public education about its plight is one of the most valuable roles a captive individual can play.

Water: 20–26°C, pH 6.5–7.5, well-oxygenated; large weekly water changes mandatory. Tank: 10 000 L minimum; open swimming space; very strong, high-capacity filtration. Feeding: Algae wafers, blanched greens, spirulina pellets, aquatic plants; herbivorous adults refuse animal protein. Breeding: Extremely rare in captivity; accomplished only at specialist Southeast Asian facilities with hormonal protocols. Compatibility: Gentle giant; suitable only with other very large, peaceful species in public-scale systems.