Freshwater Fish Harlequin Rasbora

The most interesting types of Rasboras is Harlequin Rasbora (Trigonostigma heteromorpha). The specific name "heteromorpha", was translating from the Greek as "differently shaped". The freshwater tropical fish species native from Southeast Asia is an extremely desirable aquarium addition thanks to its gorgeous metallic coloration and ease of care. It's not difficult to see why so many hobbyists treasure Harlequin Rasbora . A large school of Harlequin Rasboras with the size up to 5 cm fill the upper areas of the aquarium. The movement and color so lively and vibrant that even non-hobbyists marvel at the display.

A member of Cyprinidae family, Harlequin Rasbora is easily identified by its characteristic black "pork chop" shaped patch and beautifully lustrous copper/orange body. The distinguishing triangular patch begins near the dorsal fin and comes to a point near the base of the caudal fin. The patch on the male Harlequin Rasbora is slightly rounded at the bottom with an extended tip. In contrast, the patch on the female Harlequin Rasbora is straight. The female Harlequin Rasbora is also larger than the male.

The Harlequin Rasbora does best in an established planted aquarium with open areas for swimming. The Harlequin Rasbora should be kept in schools of 8-10 individuals and housed with other small, peaceful fish. The tanks should be decorated with plenty of room to swim and hide; plants can be used as shelter too. This beautiful freshwater tropical fish for aquascape will benefit from soft water. The mild nature of the Harlequin Rasboras makes it a great community fish.


For Rasbora heteromorpha generally spawns on the undersides of broad-leaved plants. A breeding tank with shallow, warm, acidic, soft water with broad-leaved plants should be set up. To encourage spawning, pair a young (9-12 months old) female Harlequin Rasbora with a two-year old male and offer live food items. After spawning, remove the parents and keep the aquarium dark until the eggs hatch (after about 24 hours). Feed the fry infusoria.

Omnivore, in the wild the Rasbora harlequin feeds on aquatic invertebrates and small insects in captivity it will accept almost everything offered, flake food, frozen food and freeze-dried food. Feeding should be provided at least two times a day.