Bala Shark Care Guide - Aquarium Size, Diet & Breeding

The Bala Shark is a streamlined, silver-bodied freshwater fish with a sharply forked tail and black-edged fins. Despite its common name, it is not a marine shark; the name refers to its sleek profile and prominent dorsal fin. Its reflective scales and confident swimming style make it an eye-catching feature fish.

Bala Sharks are native to mainland and island Southeast Asia, including parts of the Mekong and Chao Phraya basins, the Malay Peninsula, Sumatra and Borneo. Wild populations inhabit large rivers, tributaries and associated floodplain waters, although the species has disappeared from or become scarce in parts of its former range.

A group of adult Bala Sharks needs a very large, fully covered aquarium of at least 750 litres, with a preferred footprint of around 240 cm by 90 cm or larger; smaller tanks are only suitable for juveniles temporarily. Provide strong filtration, good oxygenation and generous open swimming space, while using sturdy wood, smooth rocks and hardy plants around the edges to leave the centre unobstructed. A secure lid is essential because these powerful fish can jump, and a smooth sand or fine-gravel substrate helps prevent injury.

Up to 35 cm (14 in) in total length. Females are often slightly deeper-bodied and may grow a little larger than males, although sex-based size differences are not always obvious.

Bala Sharks are omnivorous opportunists. Offer a varied diet of quality sinking or floating pellets and flakes, supplemented with frozen or live foods such as bloodworms, brine shrimp, mysis shrimp and chopped earthworm. Blanched vegetables and occasional algae-based foods can add useful variety, while several modest meals help support active, fast-growing fish.

Bala Sharks are generally peaceful and can live with similarly peaceful, robust fish such as large rasboras, giant danios, peaceful barbs, larger gouramis, rainbowfish and suitable medium-to-large catfish. They should not be housed with tiny fish that could be swallowed, fin-nipping species, highly aggressive cichlids or delicate, slow-moving tankmates. Their eventual size and energetic swimming also make them unsuitable for most typical community aquariums.

Bala Sharks are egg-scattering spawners and are rarely bred in ordinary home aquariums. Mature adults may spawn after seasonal changes in water conditions, with eggs released among fine-leaved plants or spawning media and fertilised externally. Commercial breeding generally relies on very large ponds or tanks and, in some cases, hormonal techniques. The adults should be removed after spawning because they may eat the eggs or fry.

Adult females are usually fuller through the belly, while males tend to be slightly slimmer and may have a more streamlined appearance. The differences are subtle, especially in young fish, and reliable sexing can be difficult outside mature breeding groups.