Rasbora

Rasbora is a genus of small freshwater fish in the family Cyprinidae, native to streams, rivers, and wetlands across South and Southeast Asia. In the aquarium hobby, rasboras are admired for their peaceful behavior, schooling tendencies, and varied color patterns. Most species are a few centimeters in length, with body shapes and hues that range from silvery tones to metallic blues, greens, or oranges.

Habitat and distribution: Rasboras inhabit a variety of freshwater environments, from clear upland streams to slower backwaters and flooded forests. They are distributed from Sri Lanka and the Indian subcontinent through Southeast Asia to Indonesia and nearby regions. They typically prefer well-oxygenated water and vegetation or leaf litter that provides cover and feeding opportunities.

Biology and behavior: Rasboras are schooling fish that form sizeable groups in the wild and in captivity. They are omnivorous, feeding on small invertebrates, zooplankton, algae, and plant matter. In aquariums, they do best when kept in groups with compatible, similarly sized tank mates. Reproduction is usually via egg scattering among plants or substrate; adults do not guard the spawning site, and the eggs hatch after about one to two days, depending on conditions.

Taxonomy and notes: Rasbora is a large genus within Cyprinidae, and some fish commonly sold as rasboras belong to closely related genera. A well-known example in the hobby is the harlequin rasbora, which is now classified as Trigonostigma heteromorpha, though it is frequently referred to as a rasbora by hobbyists.

Conservation: Habitat degradation and over-collection in some regions have affected local populations, but many Rasbora species are widespread and not currently listed as threatened.