Description
Forktail Rainbowfish (Pseudomugil furcatus)
π Basic Info
Scientific Name: Pseudomugil furcatus
Common Names: Forktail Blue-eye, Forktail Rainbowfish, Furcata Rainbowfish
Family: Pseudomugilidae (Blue-eyes)
Order: Atheriniformes
Origin: Papua New Guinea β found in rainforest streams, clear creeks, and shallow backwaters
Size: Up to 2.5 inches (6 cm)
Lifespan: 3 β 5 years
Tank Zone: Upper and mid-water swimmer
π Water Parameters
TDS: 120 β 250 ppm
pH: 6.0 β 7.5
Temperature: 24 β 28Β°C (75 β 82Β°F)
Hardness: 5 β 12 dGH
π Characteristics
Body: Slender, semi-transparent body with iridescent yellow-silver sheen and a distinctly forked tail.
Fins: Males show bright yellow fins with black edges and striking blue eyes.
Females: Smaller, paler, and less colorful than males.
Behavior: Energetic and peaceful schooling fish; enjoys open swimming space and mild current.
Display: Males display and flare fins to each other and females β stunning to watch in planted tanks.
π½οΈ Food
Type: Omnivorous (micro-predator)
Diet: Crushed flakes, micro-pellets, live or frozen baby brine shrimp, daphnia, cyclops, and fine frozen foods.
Feeding Frequency: 2β3 small feedings daily.
Tip: Provide live food often to enhance color and breeding activity.
π οΈ Maintenance
Tank Size: Minimum 20 gallons (75 L) for a group.
Filtration: Gentle filtration with mild current; sponge or canister filters are ideal.
Decor: Well-planted tank with fine-leaved plants (Java Moss, Cabomba) and open swimming areas.
Lighting: Moderate to bright; helps display colors beautifully.
Water Change: 20β30% weekly with stable water conditions.
π₯ Social Behavior
Group Size: Keep in groups of at least 8β10 for natural behavior and best color display.
Tank Mates: Peaceful community fish like Tetras, Rasboras, Corydoras, and Shrimp.
Avoid: Aggressive or fin-nipping fish.
β Doβs
β’ Keep in groups for active schooling behavior
β’ Feed live and frozen foods for best coloration
β’ Maintain clean, stable, warm water
β’ Provide plants and floating cover for comfort
β Donβts
β’ Donβt mix with large or aggressive species
β’ Donβt expose to strong water currents
β’ Donβt allow big water parameter changes
β Quick Tips
The Forktail Rainbowfish (Pseudomugil furcatus) is a small, dazzling species known for its forked yellow tail, blue eyes, and lively behavior. Itβs perfect for planted community tanks and thrives in soft, slightly warm water. Keeping a group ensures bright coloration and playful displays β an ideal choice for nano and aquascaped aquariums.







