River Catfish

Hemibagrus nemurus is a large and widespread bagrid catfish found across Thailand, Malaysia, Indonesia, and Vietnam, inhabiting major river systems, large reservoirs, and deep pools. It is a robust, fast-growing predator with a deeply forked caudal fin, large head, and wide gape that enable it to capture substantial prey. Like H. wyckioides, it is an important food fish across Southeast Asia as well as an occasional aquarium subject.

In the aquarium, Hemibagrus nemurus requires very large facilities and powerful filtration. It is an active swimmer that occupies the lower and mid sections of the water column, and it will pursue and consume fish of considerable size once mature. Despite its predatory nature, it can be a rewarding species for the specialist — personable, bold, and visually striking with its silvery-bronze coloration and imposing build.

Feed with whole fish, large prawns, earthworms, and other meaty foods. The species is aggressive toward smaller tankmates and must be housed with species of comparable or greater size. Regular, large water changes and efficient biological filtration are non-negotiable for long-term success with this demanding but spectacular catfish.

Water: 22–28°C, pH 6.0–7.5, soft to moderately hard (GH 2–15); powerful filtration and oxygenation required. Tank: 600 L minimum; industrial-grade filtration; minimal sharp decor; open swimming lanes. Feeding: Whole fish, large prawns, earthworms, fish fillet; feed 2–3 times weekly. Breeding: Not achieved in home aquaria. Compatibility: Aggressive; keep with large robust species only; will consume medium-sized fish.