Forktail blue-eye

Pseudomugil furcatus

Also known as Forktail furcata blue eye rainbowfish

FreshwaterFish

Forktail blue-eye (Pseudomugil furcatus) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 75–82°F; 24–28°C
pH: 6.0–7.5
Adult size: 2.2 in; 5.5 cm
Minimum tank: 22 gal; 85 L

Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: Hard
Rarity: Rare
Family: Pseudomugilidae
Origin: New Guinea

Overview

Forktail blue-eyes are small, peaceful fish that show best in a group of eight to ten, where the males constantly display their yellow-and-black forked tails and raised fins to each other. They keep to the middle and upper water and belong with other gentle, similarly sized fish rather than anything pushy. Feed small, frequent meals of micro pellet, crushed flake, frozen cyclops, daphnia, and baby brine shrimp to keep their color and energy up. They appreciate fine-leaved plants and steady, clean water. Aim for a tank around 85 liters or larger.

In the wild

This blue-eye comes from clear rainforest streams in eastern New Guinea, where it lives in cooler, well-oxygenated running water among plants and roots. Those streams are soft and slightly acidic to neutral, fitting a pH of about 6 to 7.5 and a temperature between 24 and 28 degrees Celsius. Recreate the setting with fine substrate, plenty of fine-leaved and floating plants, some wood, and gentle, clean flow to keep oxygen high.

Good to know

Pseudomugil furcatus belongs to the blue-eye family Pseudomugilidae and reaches about 5.5 centimeters, with males a little larger and more decorated than females. The name furcatus means forked, for the deeply split tail that flashes yellow and black when a male displays. It is a continuous egg-scatterer that lays small eggs among fine plants and mops over weeks, with no care for eggs or young. The very small fry need tiny first foods, which puts breeding on the harder side.

Did you know

Forktail blue-eyes were once placed in their own genus called Popondetta, after the town in New Guinea near where they were found, and older books still list them under that name. Males spend much of the day fanning their forked tails at rivals.

Weekly picks

Tank mates

Forktail 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