Irian Rainbowfish

About

The Irian Rainbowfish (Melanotaenia irianjaya) is a seldom-encountered species that doesn't show up in fish stores nearly as often as it deserves. Native to rainforest creeks and small rivers in Indonesian New Guinea, it shares the active, sociable nature typical of the rainbowfish family but carries one distinctive physical trait worth knowing: the middle rays of both the dorsal and anal fins are noticeably elongated compared to the rest, a feature more commonly associated with the closely related Glossolepis genus. That quirk alone makes it an interesting addition for anyone who keeps rainbowfish and wants something a little different. Like all rainbowfish, it really comes into its own when kept in a group of at least six to eight, and males will display their best coloration when competing for attention among themselves. It's a peaceful fish, though it does best alongside species that share similar water chemistry preferences. Other rainbowfish, danios, barbs, characins, and bottom-dwellers like Corydoras are all sensible companions. Skittishness is common in the family, so a well-planted tank with plenty of open swimming space helps keep the fish settled. This is a rewarding and manageable species, accessible even to newer keepers who are comfortable maintaining a community setup.