Rainbow Shark

About

The rainbow shark (Epalzeorhynchos frenatus) is a sleek, dark-bodied fish from the river systems of Southeast Asia. The Mekong, Chao Phraya, Maeklong, and Xe Bangfai basins among them. In the wild it occupies midwater and bottom zones near solid surfaces in rivers and streams, moving into flooded areas during wet seasons before retreating back as waters recede. Its diet in nature leans heavily on algae and plant matter, with some small invertebrates mixed in, and it carries that same grazing tendency into the aquarium. The deep charcoal body set against vivid red-orange fins makes it one of the more visually distinct fish in the freshwater hobby, and the albino form, white body, red fins, is equally popular. What you need to know going in is that this fish has a temper. It is territorial and will harass tankmates that stray into its claimed space, particularly fish with a similar body shape or coloration. Keeping it alongside a red-tailed shark is asking for trouble. In a larger, well-decorated aquarium with plenty of hiding spots and broken sightlines, it can coexist with dissimilar species reasonably well. This is an intermediate-level fish that rewards thoughtful stocking decisions and a bit of extra planning.