Common Name: Harlequin Fish, Red Rasbora, Rasbora
Scientific Name: Rasbora Heteromorpha (DUNCKER, 1904)
Pronounced: Raz-bo'ra het'er-o-morf"a
Meaning of Name: Rasbora, a native name; heteromorpha, differing in shape (from most members of the genus)
Categories: Cyprinidae, Cyprinid
Origins: Thailand, Malay Peninsula and Sumatra. Mostly small bodies of water in the rain forest regions.

Description: Up to 1 3/4 - 2 inches. Lives about 5 years. Should be kept in a school of eight or more. Likes the middle to upper layer of the tank. In comparison to other Rasboras, the Harlequin Fish is stocky and tall with a convex underside.
 They are a silverish with a blackish blue tiangular-shaped mark beginning in the mid-section and becoming narrower and extending almost to the caudal fin. Their eyes have a bright red glow. The dorsal fin is a vivid red with a yellow tip. The caudal fins top and bottom edges are a bright red while the inner rays are yellowish and the rear edge colorless. It is a peaceful fish, although males tend to have occasional disputes.
 The sexes can be distinquished by their markings. The females have a straight edge to the black marking and the lower front corner is indistinct; while it has a sharp edge and is slightly rounded at the bottom and the tip is extended more towards the belly in the males. The male is, as a whole, more brightly colored. During breeding time he will take on a crimson to purplish flush. The male is also more slender than the female.
Diet: Omnivorous. Flake, frozen, and preferably live foods of all kind, particularly small crustaceans and midge larvae.
Environment: Water temperature between 72-80F., preferably filtered thru peat pH 5.5-7.5, dH 6 to 10.
Tank Mates: Planted community tank.
Breeding: Not easy to breed. It was for a long time impossible to breed, but now it is commonly done if the right conditons are met. Use a year old female with a two year old male. Condition the breeders by feeding them white worms and brine shrimp. The water temperature should be between 78-82F., and should have a pH of 6 and a dH 1.5 - 2.5 in a deep, long tank as they require plenty of space for spawning. The spawning tank should also have a dark substrate, and be well planted.
 The spawning is stimulated by sunlight where the male will then entice the female to the spawning site. A number of false spawns and some high spirited chasing is done prior to the actual mating. The actual spawn may not take place for a few days. The male will curl his caudal penduncle around the female which is in an upside down position, at which time the pair will deposit several small clear eggs on the underside of broad leaved plants, such as Crytocoryne, Sagattaria, Bacopa, and Lagenandra. The spawning will be repeated several times under different leaves, for a period of about two hours, at which time between thirty and eighty eggs will have been deposited.
 The parents are egg eaters, so it is best to remove them to the maintenance tank. Lower the water level in the spawning tank to four or five inches. The eggs will hatch in 24-30 hours producing very small fry. In three to five days, the fry will reach the free swimming stage and can be fed rotifers and nauplii graduating to Artemia larvae. Frequent water changes are recommended.