Lake Furnusu rainbowfish

Melanotaenia mairasi

Also known as Mairasi rainbowfish

FreshwaterFish

Lake Furnusu rainbowfish (Melanotaenia mairasi) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 77–86°F (25–30°C)
pH: 6.8–8.0
Adult size: 2.4 in (6.2 cm)
Minimum tank: 29 gal (110 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: Medium
Rarity: Rare
Origin: Lake Furnusu, West Papua, Indonesia
Family: Melanotaeniidae

Overview

A dwarf rainbowfish for a modest tank, best kept in a slightly larger school of eight or more small fish so the group feels secure and the males display. It is peaceful and suits a small community of gentle tankmates rather than large or pushy fish. Feed fine foods: crushed flake, small granules, and frozen or live daphnia, cyclops, and baby brine shrimp. A tank of around 110 liters with plenty of plants and gentle open water suits a dwarf school.

In the wild

The Lake Furnusu rainbowfish is endemic to a small lake in the Mairasi tribal lands of West Papua. Keep it warm, 25 to 30 degrees Celsius, in neutral to alkaline water at a pH of 6.8 to 8.0. A densely planted tank with soft substrate, gentle flow, and open patches of water mimics its quiet lake home and shows the golden body at its best.

Good to know

Melanotaenia mairasi, family Melanotaeniidae, was described by Allen and Hadiaty in 2011 and stays around 6 centimeters, one of the smaller rainbowfishes. It carries a golden body marked with dusky bands. The name honors the Mairasi people, on whose land the lake sits. Breeding is of medium difficulty, the fish scattering adhesive eggs among fine plants or mops over several days.

Did you know

The lake it comes from was unsurveyed by scientists until a 2010 expedition; within a year the fish had a name honoring the Mairasi people who guided the researchers in.

Tank mates

Lake Furnusu rainbowfish is a peaceful, schooling species that keeps to the middle. These picks match on water type, temperature, pH, size and temperament.