Blue axelrodi rasbora

The blue axelrodi rasbora (Sundadanio axelrodi) is a tiny freshwater cyprinid of the family Danionidae, native to blackwater peat swamps and forest streams of Borneo and Sumatra. It has a slender, translucent body that shows shimmering blue-green flanks and red or orange fins, with color varying between regional forms. Its small size and delicate coloration make it a popular nano-aquarium fish. It is a peaceful, shoaling species that must be kept in groups of at least eight to ten to feel secure and display color. It suits only very calm, small tankmates. A densely planted nano aquarium with soft, acidic blackwater conditions, gentle filtration, and subdued lighting is important, as this species is sensitive to hard or unstable water. It takes small foods such as micro-pellets, crushed flakes, and tiny live or frozen items. It is delicate and best suited to experienced keepers. Breeding is possible but challenging.