TankBud

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
Egg depositor · Medium
Rarity
Rare
Family
Melanotaeniidae
Origin
Lake Furnusu, West Papua, Indonesia

Overview

The Lake Furnusu rainbowfish is a peaceful dwarf rainbowfish that schools in the middle of a modest planted tank. It is best with a little experience.

Did you know

Lake Furnusu had never been surveyed by scientists until an expedition in 2010. Within a year, the fish had a name honoring the Mairasi people, who guided the researchers in.

Caring for the Lake Furnusu rainbowfish

Keep Lake Furnusu rainbowfish in a school of eight or more, in a tank of 29 gal (110 L) or larger. A larger school helps the group feel secure and gets the males displaying. Plant the tank densely over a soft substrate, and leave open patches of water with a gentle flow. That setup mimics their quiet lake home and shows the golden body at its best.

Keep the water warm and neutral to alkaline, at 77 to 86°F (25 to 30°C) and a pH of 6.8 to 8.0. Feed fine foods, such as crushed flake and small granules, with frozen or live daphnia, cyclops and baby brine shrimp.

Lake Furnusu rainbowfish are peaceful and suit a small community of gentle tank mates. Keep them away from large or pushy fish. Breeding them is of medium difficulty. They scatter adhesive eggs among fine plants or mops over several days.

Good to know

Melanotaenia mairasi is a member of the family Melanotaeniidae, described by Allen and Hadiaty in 2011. It is one of the smaller rainbowfishes, and its golden body is marked with dusky bands. Some keepers call it the Mairasi rainbowfish.

In the wild

The Lake Furnusu rainbowfish is endemic to Lake Furnusu, a small, quiet lake in West Papua, Indonesia. The lake lies in the tribal lands of the Mairasi people.

Weekly picks

Tank mates

The Lake Furnusu rainbowfish is a peaceful, schooling species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a Lake Furnusu rainbowfish need?

A Lake Furnusu rainbowfish needs at least 29 gal (110 L). It spends most of its time in the middle.

What temperature and pH does a Lake Furnusu rainbowfish need?

A Lake Furnusu rainbowfish is comfortable at 77–86°F (25–30°C) with a pH of 6.8–8.0.

What does a Lake Furnusu rainbowfish eat?

A Lake Furnusu rainbowfish eats fine foods such as crushed flake and small granules. Give it frozen or live daphnia, cyclops and baby brine shrimp as well.

How big does a Lake Furnusu rainbowfish get?

An adult Lake Furnusu rainbowfish reaches about 2.4 in (6.2 cm).

Does a Lake Furnusu rainbowfish need a group?

Yes. A Lake Furnusu rainbowfish is a schooling species and should be kept in a group, not singly.

How does a Lake Furnusu rainbowfish breed?

Lake Furnusu rainbowfish scatter adhesive eggs among fine plants or mops over several days. Breeding them is of medium difficulty.

Related species