Spotted blue-eye

Pseudomugil gertrudae

Also known as Gertrudae Rainbow

FreshwaterFish

Spotted blue-eye (Pseudomugil gertrudae) — Der Regenbogenfisch (Diskussion) · CC BY-SA 3.0 de

Care at a glance

Temperature: 70–82°F; 21–28°C
pH: 6.0–7.5
Adult size: 1.5 in; 3.8 cm
Minimum tank: 17 gal; 65 L

Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: Medium
Rarity: Rare
Family: Pseudomugilidae
Origin: Australia, Aru Islands

Overview

Spotted blue-eyes are tiny, gentle fish that do best in a group of eight or more, where the males constantly flick and spread their spotted fins in display. They swim in the middle and upper water and need equally small, calm tankmates, or a species-only tank of their own, since anything bigger will outcompete or eat them. Feed small foods often, such as crushed flake, frozen cyclops, daphnia, and baby brine shrimp. They love soft, slightly acidic water thick with fine and floating plants. Aim for a tank around 65 liters or larger.

In the wild

This little blue-eye lives across northern Australia and the Aru Islands, in soft, tannin-stained pools, swamps, and slow streams full of plants. The water runs acidic to neutral and soft, matching a pH of about 6 to 7.5 and a temperature between 21 and 28 degrees Celsius. Recreate it with dark substrate, leaf litter or wood for a gentle tea color, dense fine-leaved and floating plants, and calm, clean water.

Good to know

Pseudomugil gertrudae belongs to the blue-eye family Pseudomugilidae and is one of the smallest at about 3.8 centimeters. Males carry rows of dark spots across clear, feathered fins that they raise in display. It scatters small eggs among fine plants and mops over a long spawning period, and while it needs small first foods and steady water, keepers rate its breeding as moderate, easier than many of its relatives. Parents give no care and will eat their own eggs.

Did you know

Spotted blue-eyes come in several regional forms with different fin patterns and spot counts, and keepers often keep the strains apart to preserve them. Despite being under four centimeters long, the males put on near-constant fin displays.

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Tank mates

Spotted blue-eye 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