TankBud

Western rainbowfish

Melanotaenia australis

Also known as Melanotaenia splendida australis

FreshwaterFish

Western rainbowfish (Melanotaenia australis)
laurent MARSOL - Aussie Oc (talk) · CC BY-SA 3.0

Care at a glance

Temperature
72–81°F
22–27°C
pH
6.5–8.0
Adult size
4.7 in
12 cm
Minimum tank
30 gal
115 L
Temperament
Peaceful
Social behavior
Schooling
Swim level
Middle
Difficulty
Medium
Breeding
Hard
Rarity
Very rare
Family
Melanotaeniidae
Origin
Australia

Overview

Western rainbowfish are hardy, active schoolers that do well in a group of six or more, with extra males adding to the color and fin displays. They swim in the middle of the tank and stay peaceful with other sturdy community fish of similar size. They adapt to a range of conditions and reward good feeding with brighter color, so offer varied meals of flake or pellet, frozen bloodworms, daphnia, and brine shrimp. Plant the sides and back and keep the center open for swimming. Aim for a tank around 115 liters or larger.

In the wild

This rainbowfish is widespread across northwestern Australia, including the Kimberley and Pilbara, where it lives in streams, gorges, pools, and billabongs that can range from clear to seasonal and turbid. It takes warm, neutral to slightly hard water, matching a pH of about 6.5 to 8 and a temperature between 22 and 27 degrees Celsius. Recreate it with fine substrate, rock and wood, hardy plants around the edges, and clean water with gentle flow.

Good to know

Melanotaenia australis is a member of Melanotaeniidae and grows to around 12 centimeters. It is a variable fish, with color differing between the many river and gorge systems it occupies across northwestern Australia. Males are deeper bodied and more colorful than females. Like other rainbowfish it is a continuous egg-scatterer, laying a few eggs a day onto fine plants and mops over a long season, with the slow-growing fry making breeding hard.

Did you know

The western rainbowfish is one of the most widespread freshwater fish in northwestern Australia, turning up in everything from permanent gorge pools to creeks that all but dry up in the dry season. Each isolated system tends to hold its own color form.

Weekly picks

Tank mates

Western 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 Western rainbowfish need?

A Western rainbowfish needs at least 30 gal (115 L). It spends most of its time in the middle.

What temperature and pH does a Western rainbowfish need?

A Western rainbowfish is comfortable at 72–81°F (22–27°C) with a pH of 6.5–8.0.

How big does a Western rainbowfish get?

An adult Western rainbowfish reaches about 4.7 in (12 cm).

Does a Western rainbowfish need a group?

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

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