Sepik rainbowfish

Care at a glance

Overview

Keep them in a group of six or more, with at least two to three females per male to spread out aggression and bring out the males' color. They are fast, active swimmers that cruise the middle of the water column all day, so the tank needs a long footprint, around 120 cm or more, and at least 208 liters. Hold the water warm at 26 to 30 C, soft, and acidic at pH 6.2 to 6.8. They are mostly peaceful but can dominate smaller or more timid rainbowfish, so pair them with similarly sized, robust tankmates. Feed a varied diet of quality flakes or small pellets plus frozen foods like daphnia and bloodworms. They are strictly freshwater, so no salt or brackish conditions.

In the wild

Sepik rainbowfish come from the river floodplains of northern New Guinea, across the Sepik, Ramu, and Mamberamo systems in Papua New Guinea and Western Papua, Indonesia. These are warm, soft, slightly acidic waters, which is unusual for a rainbowfish, since most of the family prefers harder, alkaline conditions. Give them a long, planted tank of at least 208 liters with open swimming space down the middle and dense planting along the back and sides. Keep the water warm at 26 to 30 C, soft, and on the acidic side at pH 6.2 to 6.8, and do not keep them in alkaline water. Add a little current and keep oxygen levels high.

Good to know

This is Glossolepis multisquamata, a rainbowfish in the family Melanotaeniidae. Adults reach about 14 cm, which makes them one of the larger rainbowfish. They are continuous plant-spawners that scatter eggs into fine-leaved plants over and over rather than in one batch, and they live a long time for an aquarium fish, up to around 10 years.

Did you know

Most rainbowfish want neutral to hard, alkaline water, but this one is the odd one out. As a floodplain fish it actually does best in soft, slightly acidic water and will struggle in the alkaline conditions that suit its relatives. The breeding is the easy part once they are well fed, but the eggs hatch into tiny fry, and growing those out is where most keepers get stuck.

Related species

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  Eastern rainbowfish

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  Parkinson's rainbowfish

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