Climbing Perch

About

The climbing perch (Anabas testudineus) is one of the more unusual freshwater fish a hobbyist can keep, and its reputation for being able to leave the water and travel overland is entirely deserved. Native to a vast stretch of Asia from India to the Wallace Line, it occupies an enormous range of habitats. Canals, swamps, flooded rice paddies, estuaries, and stagnant pools with low oxygen levels that would be fatal to most other fish. It manages this through a well-developed labyrinth organ, the most complex of any anabantid relative to body size, which allows it to breathe atmospheric air directly. Given a damp surface, an individual can survive out of water for days or even weeks. In the wild it migrates with seasonal floods and buries itself in mud during dry spells. For the aquarium it presents a genuine challenge. This is a large, predatory, and often territorial fish that will consume anything small enough to fit in its mouth, and it is a confirmed jumper, so a secure lid is non-negotiable. Tankmate options are limited to robust, similarly-sized species. Reports on intraspecific aggression vary considerably, possibly because the genus contains multiple undescribed species currently lumped under one name. Experienced keepers who appreciate odd, capable fish will find it rewarding, but it is not a community tank resident.