Forktail blue-eye
Pseudomugil furcatus
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
- Origin
- New Guinea
- Family
- Pseudomugilidae
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.
Where to buy
Some links may not be the exact species or variety.
- Aquatic Arts Freshwater fish, shrimp and snails with an arrive-alive guarantee
- Flip Aquatics Quarantined shrimp, snails and nano fish
- Imperial Tropicals Freshwater fish and inverts bred at a Florida hatchery
- Aqua Huna Freshwater fish, shrimp and plants with a three day live arrival guarantee
…or ask your local fish store.
Appears in
Freshwater fish · Rainbowfish · Schooling fish · Community fish
Keeping Forktail blue-eye?
Track water tests, reminders and stocking fit.
Related species

Delicate blue-eye
Pseudomugil tenellus2.2 in (5.5 cm)20 gal (75 L)77–90°F (25–32°C)
Pacific blue-eye
Pseudomugil signifer2.8 in (7 cm)25 gal (95 L)68–79°F (20–26°C)
Spotted blue-eye
Pseudomugil gertrudae1.5 in (3.8 cm)17 gal (65 L)70–82°F (21–28°C)Popondetta blue-eye
Pseudomugil connieae2 in (5 cm)11 gal (40 L)75–82°F (24–28°C)Honey blue-eye
Pseudomugil mellis1.4 in (3.5 cm)11 gal (40 L)68–82°F (20–28°C)Paska's blue-eye
Pseudomugil paskai1.4 in (3.5 cm)11 gal (40 L)72–79°F (22–26°C)
