Lake Wanam Rainbowfish

About

The Lake Wanam Rainbowfish (Glossolepis wanamensis) comes from one of the most restricted ranges of any fish in the hobby. A single small crater lake on a plateau near Lae, Papua New Guinea. That isolation makes it something genuinely special to keep, but also something of a responsibility. Wild populations have declined sharply due to introduced species like tilapia and carp, and the species is now considered critically endangered. A captive breeding program exists, and the fish does appear occasionally through hobbyist networks, though there are ongoing concerns that some captive stock may have hybridized with the closely related Glossolepis multisquamata, so sourcing from reputable breeders matters. In the aquarium, this is a peaceful, active mid-water fish that moves quickly and confidently through open water. That energy is rarely a problem, though it can fluster very small or sluggish tankmates. A group of six or more is really the way to go. They settle better, show less skittishness, and the males put on a noticeably better color display when they have rivals to posture at. Other rainbowfish, danios, barbs, and hard-water tolerant catfish all make sensible companions. Care is intermediate. Not difficult, but this fish does best with consistent water quality and a keeper who pays attention.