Banded rainbowfish

Melanotaenia trifasciata

FreshwaterFish

Care at a glance

Temperature: 75–84°F (24–29°C)
pH: 6.5–8.0
Adult size: 5.9 in (15 cm)
Minimum tank: 50 gal (190 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Easy
Breeding: Hard
Rarity: Rare
Origin: Australia
Family: Melanotaeniidae

Overview

Banded rainbowfish are active, sizeable fish that do best in a group of six or more, where males compete in color and fin displays without any real aggression. They cruise the middle of the tank and suit a spacious community with other robust, peaceful species. Because they can reach around 15 centimeters and swim hard, give them length to move. Feed a varied diet of good flake or pellet with frozen bloodworms, brine shrimp, and the odd bit of vegetable matter. Densely plant the back and sides and keep a long open lane in front. Aim for a tank around 190 liters or larger.

In the wild

This rainbowfish lives across northern Australia, in clear coastal and inland streams that run over sand and stone with plenty of sunlight and aquatic growth. Those waters are typically warm and neutral to slightly hard, so a pH of about 6.5 to 8 and a temperature between 24 and 29 degrees Celsius fit it well. Set up an aquarium with a fine substrate, driftwood or rockwork, sturdy plants along the margins, and clean, well-filtered water with a little current to mimic the flow it knows.

Good to know

Melanotaenia trifasciata sits in the family Melanotaeniidae and is one of the larger members, reaching up to about 15 centimeters though it is often seen a little smaller. The scientific name refers to the dark band that runs the length of the body, and populations from different rivers vary widely in base color. It is a continuous egg-scatterer, dropping a small number of eggs daily onto fine plants or wool mops over weeks. Coaxing a good spawn and raising the tiny fry takes effort, so breeding is considered hard.

Did you know

Banded rainbowfish are well known among keepers for their regional color forms, with names like Goyder River pointing to the exact creek a strain came from. Two fish of the same species can look strikingly different depending on where their line originated.