Harlequin rasbora
Tropical fish profilesCommon name: Rasbora ; there are many rasbora species, but harlequin rasbora is the most popular in tropical fish aquariums.
Scientific name: Rasbora heteromorpha
Family: Cyprinidae
In nature: Thailand, Eastern Sumatra, Malaysia, Indonesia. Rasboras inhabit clear, acidic, tropical forest streams. They are endangered in the natural environment. Harlequin Rasbora was discovered in 1902 by a german ichthyologist in the Singapore Botanic Gardens.
Social: timid, peaceful, lively, schooling fish, the more individuals the better. Pretty hardy, they are good fish for the beginners. They are peaceful toward other fish.
Swimming in the aquarium: they need open space for swimming and schooling behavior. They swim to the surface and in the midwater areas of the aquarium.
Feeding: They accept a variety of foods, flakes and frozen foods are fine but as usual, some live food treat will make them very happy.
Water temperature: 73 to 82 F (22 to 25 C)
Water pH: their natural environment has soft, slightly acidic water; optimal pH is 6.0-7.5.
Water hardness: 1-3 dH
Description: Rasboras are often used in aquascaping, to populate big planted tanks, since their schooling behavior and elegance complement such tanks very nicely. Unlike other Rasbora species, Harlequin Rasbora is stocky and has a convex belly. Males are slim compared to the females. They are pretty small as adults, about one and three quarter inches (4,5 cm).
Their coppery-silver color look magnificent in the light. You can easily notice a triangular black spot that begins wide in the center of the body and becomes narrower as it extends to the caudal fin. The lower front of the triangle is often indistinct in females, while in the males it is sharp and extends down to the belly. The dorsal fin has a yellow tip. The upper and lower tips of the caudal fin are red.
Behavior: The larger is the tank, the better – in small tanks or in community aquariums with many other fish, they usually do not display schooling behavior. In my opinion, the schooling behavior is one of the most fascinating aspects of these fish and should be stimulated as much as possible. Adding 1-2 large (but peaceful) fish will trigger the schooling behavior or intensify it, since rasboras consider those big fish predators, and it is a known fact that schooling is the natural strategy for survival in small prey.
See what I mean? My rasboras stay together because of the BIG angel fish that they consider a predator :).
I love to see them following each other as a team.
Rasbora as schooling fish
Breeding
You should have females 15-30 months old because older females usually do not produce eggs. The water must have a pH of 5.3-5.7 and the temperature must range from 79 to 82°F (26 to 28°C). Cryptocoryne is the best plant you can use in the spawning tank. The water level should be lowered. Spawning can start during sunrise and takes about three hours. The female lays about 200 eggs which are usually placed under the plant leaves. Remove the parents immediately after spawning to save the eggs.
To avoid fungus, use some materials to darken the aquarium. The eggs hatch in about 24 hours and swim after 3 days. Start feeding infusoria and egg yolk. When the fry are 3-4 days old, you can feed them with artemia nauplii. The fry are very sensitive and you must change very small volumes of water during the week. The fry grow pretty fast.