Forktail Blue-eye Rainbowfish
Pseudomugil furcatus
Description
The Forktail Blue-eye Rainbowfish is a stunning species known for its iridescent, metallic body and striking blue eyes. The males are especially colorful, exhibiting a bright blue body with a red-orange hue on their fins and a forked tail, which gives them their common name. Females are generally less colorful, but still retain the shimmering metallic sheen, with a more subdued coloration. These fish have an elongated body with a forked tail that is quite prominent, and their bright, vibrant colors are accentuated by the shimmer of their scales under good lighting. Forktail Blue-eye Rainbowfish are peaceful, active swimmers that do well in schools. They are calm, non-aggressive fish, making them ideal for community aquariums.
Habitat Origin
Native to freshwater streams, rivers, and lagoons in northern Australia and Papua New Guinea, where they inhabit clear, slow-moving waters with plenty of vegetation and submerged roots. They are typically found in slightly acidic to neutral waters with moderate temperatures.
Aquarium
Ideal Number in Aquarium: At least 6 individuals, as they are schooling fish and feel more secure in groups.
Favorite Food
Forktail Blue-eye Rainbowfish are omnivores and will accept a variety of foods, including high-quality flake food, micro pellets, and live or frozen foods such as brine shrimp, daphnia, and bloodworms. They will also feed on plant matter, including algae and biofilm, which makes them excellent for planted tanks.
Behavior:
Forktail Blue-eye Rainbowfish are peaceful and non-aggressive. They are best kept in schools of at least 6 individuals, as they feel more secure and display their natural behavior when grouped together. They are active swimmers and can often be seen darting through the middle to upper sections of the tank. While they are generally peaceful, males may exhibit some territorial behavior during breeding displays. They are calm and social fish that get along with most other small, non-aggressive species.
Special Care:
These fish thrive in a well-maintained aquarium with stable water conditions. A well-planted tank with plenty of hiding spots such as driftwood, rocks, and dense plants is ideal. Forktail Blue-eye Rainbowfish prefer a moderate water flow, mimicking the slow-moving waters of their natural habitat. They do best in tanks with stable temperature, pH, and water hardness levels, so regular water changes and good filtration are important for their health.
Compatibility with Other Fish:
Yes, Forktail Blue-eye Rainbowfish are compatible with other peaceful, small species such as tetras, rasboras, and small catfish. They should not be kept with larger or aggressive fish that may stress them out or view them as food. Their peaceful nature and schooling behavior make them ideal for community tanks with other non-aggressive species that share similar water requirements.
Breeding Tank Setup
A separate breeding tank is highly recommended for Forktail Blue-eye Rainbowfish to ensure optimal conditions and protect the eggs from predation. A 10-gallon tank (38 liters) is sufficient for a small breeding group, while a 20-gallon tank (75 liters) is ideal for multiple pairs. Maintain stable water parameters: pH between 6.0–7.5, temperature of 24–28°C (75–82°F), and hardness around 4–12 dGH. Use fine sand or gravel substrate and plant the tank with Java moss, Hornwort, Anubias, and floating species like Water Sprite. A gentle sponge filter provides aeration without disturbing the delicate eggs, and moderate lighting on a 12-hour cycle simulates natural conditions.
Conditioning Adults for Breeding
Condition your breeders with a diverse, protein-rich diet to enhance egg production and vitality. Offer high-quality flakes or micro pellets, alongside live or frozen brine shrimp, daphnia, and bloodworms. Supplement with vegetable matter like chopped spinach or peas. Perform weekly 20–30% water changes, and to induce spawning, simulate a “rainy season” by increasing water change volume to 50% and raising the temperature slightly to 28°C (82°F). This mimics the natural cues that stimulate reproductive behavior in the wild.
Spawning Behavior
Spawning often occurs in the early morning, especially after a temperature shift or water change. Males will display vibrant colors and court females actively. Eggs are scattered among plants or decorations and are fertilized immediately. A female can lay 20–50 eggs per session, and the sticky eggs adhere to plant surfaces. To prevent egg loss, remove the adults after spawning, as they may eat the eggs or disturb the site, reducing hatch rates.
Fry Development
Eggs hatch in 2–3 days, depending on temperature. Newly hatched fry feed off their yolk sacs initially. After 2–3 days, begin feeding infusoria or liquid fry food. As fry grow, introduce baby brine shrimp, microworms, and eventually finely crushed flakes. Fry are sensitive to pollutants, so perform daily 10–20% water changes, keeping temperature stable between 24–28°C. Avoid overfeeding to maintain water clarity and fry survival.
Breeding Success Tips
Forktail Blue-eye Rainbowfish reach sexual maturity at 6–8 months. Males are distinguished by their intense blue coloration, especially on the forked tail and fins, and are typically more slender. Females are rounder and less colorful, particularly when gravid. Avoid stress from sudden water parameter changes or aggressive tank mates. Consistent care, proper conditioning, and a peaceful environment are essential for successful and repeatable breeding.