Pseudomugil furcatus Nichols 1955

Pseudomugil furcatus is a splendid freshwater fish, which should be kept in groups. It has very interesting behavior and reproduces very easily if kept in the right conditions. Forktail blue-eye is still often called by the old name of Popondetta furcata.

Distribution: Saffia Valley, Papua New Guinea.

Habitat: freshwater.

Submitted by
Natasha Khardina


Water Chemistry

Water information

Water type
Fresh water
Water color
Clear water
Water transparency
Concentration of sediments
Water temperature
24-26 °C
Water flow/curent

Chemical parameters

90-180 mg/l
Dissolved Oxygen


Standard length
5.0 cm
Water volume (min. aquarium)
60 l
Social behaviour
Group fish
Behaviour description

In nature this species inhabit areas of dense vegetation, so the aquarium must be decorated with many aquatic plants. Floating plants will also be appreciated, as they will help shade the light. It is also better to avoid too light backgrounds, which could annoy the fish. This species is sensitive to changes in water conditions, therefore it should absolutely not be placed in immature aquariums. The water should be hard and with a slightly alkaline or alkaline pH, as well as well oxygenated and with a gentle current.

Pseudomugil furcatus must stay in groups of at least 8-10 individuals. If the combination is carefully studied, other species can be included. It does well with Tateurndina ocellicauda, ​​with which it was found in the wild. Alternatively, other small melanotenids such as Iriatherina werneri and gobies. 

By closely mimicking their natural environment, you can create a thriving biotope aquarium that highlights the beauty and natural behavior of Pseudomugil furcatus.

Aggression grade
Day active
Sexual dimorphism

The male differs from the female by its brighter colors and fins, which grow wider. The body is predominantly gray or brownish, with a bright yellow belly. The fins have yellow-green edges and the caudal one in particular is surrounded by two colored lobes, with transparent central rays. The scales are bordered by a darker color. The eyes are blue, which is why this fish is also known as the Forktail blue-eye .

Nutrition in Nature

In Nature, Forktail blue-eye mainly consumes zooplankton, other small invertebrates and crustaceans, and food of plant origin.


Breeding tank set-up

Include plenty of live plants like Java fern and Vallisneria. Floating plants can provide shaded areas, which the fish enjoy. Add some aquatic mosses such as Java moss to create a more natural environment. Add pieces of driftwood and smooth river rocks to create hiding places and to give the tank a natural appearance.

Nutrition parents

In the aquarium, even if Pseudomugil furcatus will accept much of the dry food offered, its diet should be varied and integrate a good component of live and frozen foods.

Mating type
Spawning behaviour

The males chase the females among the vegetation and display their finnage. The few eggs are usually laid in the morning and anchored to aquatic vegetation by a thin filament, in the same way as other rainbow fish. They do not show parental care, so the eggs should be removed.

Breeding habits
Hatching period
Number of eggs in average
Parental care
Fry number
Nutrition fry

The young should be fed with infusoria until they can accept brine shrimp.

Notes on reproduction