Australian Rainbowfish (Melanotaenia splendida australis)

Melanotaenia splendida australis, the Australian Rainbowfish, is a robust and adaptable subspecies found across the rivers and billabongs of northwestern Australia including the Kimberley region and the Pilbara. It displays a beautiful blend of blue-green iridescence on the body with orange-yellow highlights on the fins, with males developing more vivid colouration as they mature and spar with rivals in display behaviour. Compared to many more specialised rainbowfish species, M. splendida australis tolerates a broader range of water conditions and is more forgiving of imperfect parameters, making it an excellent entry point into the rainbowfish family for aquarists new to the group. A social, active, and fast-moving fish that is best appreciated in groups.

Keep in groups of 6+ in a spacious, well-filtered aquarium with some current. Rainbowfish appreciate open swimming space in the middle third of the tank, with plants at the margins. Feed a varied diet of flakes, small pellets, and frequent treats of frozen daphnia, mysis, and brine shrimp. Maintain regular water changes — pristine water quality produces the most vivid colouration. Males display most brilliantly when kept with rivals.