Threadfin rainbowfish

The threadfin rainbowfish is a tiny freshwater species in the family Melanotaeniidae, native to slow, vegetated waters of northern Australia and southern New Guinea. Despite its small size, males are spectacular, with extended, filamentous dorsal and anal fin rays and a shimmering blue-silver body that flushes with color during display. It is a peaceful, active shoaling fish that spends most of its time in the upper water layers. Males constantly display their flowing fins to one another and to females, so a group with several males produces the best show. Because of its small mouth it needs finely crushed flake, micro-pellets, and small live or frozen foods such as daphnia and baby brine shrimp. It thrives in a well-planted tank with gentle flow and calm, small tankmates; boisterous or fast-feeding fish will outcompete it. It is an egg-scatterer that deposits eggs among fine plants.