The Phoenix Rasbora (Boraras merah) is a jewel of the nano aquarium world, originating from the peat swamp forests of Borneo. Reaching only 2 cm, it is one of the smallest schooling fish available to hobbyists. Males display intense red-orange to crimson body coloration with a bold black lateral stripe and black markings at the base of the caudal fin, becoming especially vivid during spawning or competition. Females are slightly larger and paler. In the wild, Phoenix Rasboras inhabit slow-moving blackwater streams and forest pools rich in tannins, fallen leaves, and dense vegetation. The water is typically very soft, acidic, and tea-colored due to decaying organic matter. In the aquarium, these conditions are replicated by using soft, filtered water with added botanicals or peat filtration. A dark substrate, driftwood, and floating plants help diffuse light and create the subdued environment they prefer. Phoenix Rasboras are best kept in groups of at least eight, and larger groups of twelve or more produce a spectacular shimmering display. They are entirely peaceful and can be kept with other micro fish, dwarf shrimp, and similarly sized tankmates. Due to their small size, they should not be housed with any fish large enough to consume them. They accept micro-pellets, baby brine shrimp, daphnia, and crushed flake foods readily in captivity.
