Pseudomugil furcatus (“Forktail Rainbowfish” / “Forktail Blue-eye”)

IUCN Red List: Not Evaluated (Localized habitat pressure from logging and sedimentation)

Imported on December 10, 2025 — shipping begins on December 22, 2025

Important note: These fish are captive-bred, making them hardy and well-suited for community aquaria.

Pseudomugil furcatus (“Forktail Rainbowfish” / “Forktail Blue-eye”)

Pseudomugil furcatus is a small, darting rainbowfish native to rainforest streams and clearwater tributaries of Papua New Guinea. Known for their forked tail, vivid yellow fins, and bright electric-blue eyes, these fish display energetic, constant movement—especially males, who perform rapid fin-flaring and chasing displays to impress females. In the wild, they inhabit shallow, vegetation-rich streams with gentle flow, strong light penetration, and dense microfauna. In aquaria, they thrive in planted setups with open swimming space and stable, clean water conditions. Their vibrant activity and striking coloration make them a standout nano schooling species.

Size:
Adults reach approximately 4–5 cm (≈ 1.6–2.0″) total length.

Water parameters:
Clean, well-oxygenated water is essential for long-term color and activity.
pH 6.0 – 7.5
GH 4 – 12 °d
KH 2 – 8 °d
TDS 80 – 200 ppm
Provide gentle flow, floating plants, and open midwater space for schooling and display behavior.

Temperature:
22 – 28 °C (72 – 82 °F); males show the best color and activity in the mid-range (24–26 °C).

Food:
Micro-predatory omnivore.
Offer:
– Baby brine shrimp
– Daphnia
– Cyclops
– Microworms
– High-quality micro-pellets and fine flakes
Frequent small feedings encourage natural display behavior and intense coloration.

Tankmates:
Peaceful and best kept in groups of 8–12+ to promote natural social structure and reduce stress.
Suitable tankmates include:
– Boraras species
– Sundadanio
– Small rasboras
– Pygmy corydoras (C. pygmaeus, C. hastatus, C. habrosus)
– Licorice gouramis (Parosphromenus)
Avoid nippy or aggressive fish that may damage their delicate fins.

Breeding:
An egg-scattering species that spawns frequently under good conditions.
Males flare brightly colored fins and court females with fluttering display movements.
Eggs are deposited in fine-leaved plants, mosses, or spawning mops and adhere to surfaces.
Adults do not guard eggs and may consume them; dedicated breeding setups increase success.
Eggs hatch in 7–14 days depending on temperature, with fry initially requiring infusoria or rotifers before transitioning to baby brine shrimp.

Important note:
These Pseudomugil furcatus are captive-bred, making them more adaptable and resilient than wild counterparts.
Maintain excellent water quality, stable parameters, and frequent small feedings to support their high activity level.
Keep them in sufficiently large groups to reduce sparring intensity and encourage natural shoaling dynamics.