Forktail Blue Eye Rainbowfish (Pseudomugil furcatus) – Bright, Active Nano Schooling Fish

Forktail Blue Eye Rainbowfish Care Guide (Pseudomugil furcatus)

The Forktail Blue Eye Rainbowfish (Pseudomugil furcatus) is a peaceful, active nano fish known for its bright yellow fins and glowing blue eyes. This species is perfect for planted aquariums and thrives when kept in small schools, making it a top choice for both beginner and experienced aquarists.

Tank Size & Setup for Forktail Blue Eye Rainbowfish

Forktail Blue Eye Rainbowfish do best in well-planted aquariums that mimic their natural habitat.

• Minimum tank size: 10 gallons (20+ gallons recommended for groups)
• Aquascape: Dense plants, driftwood, and open swimming space
• Substrate: Sand or fine gravel
• Flow: Moderate (they enjoy gentle current)
• Lighting: Moderate to high (enhances coloration)

Heavily planted tanks help reduce stress and bring out their best colors.

Water Parameters for Forktail Blue Eye Rainbowfish

Stable water conditions are key to keeping your Forktail Rainbowfish healthy.

• Temperature: 72–80°F
• pH: 6.5–7.5
• Hardness: Soft to moderately hard water
• Water changes: 20–30% weekly

Consistency matters more than chasing exact numbers.

Behavior & Temperament

Forktail Blue Eye Rainbowfish are peaceful, social schooling fish.

• Best kept in groups of 6 or more
• Males display vibrant colors and may spar harmlessly
• Extremely active swimmers that use all areas of the tank

Keeping them in groups reduces stress and improves coloration.

Diet & Feeding for Forktail Blue Eye Rainbowfish

These fish are easy to feed and not picky.

• High-quality micro pellets or flakes
• Frozen foods (brine shrimp, daphnia, bloodworms)
• Live foods for optimal color and breeding

Feed 1–2 times daily in small portions.

A varied diet will maximize color and overall health.

Breeding Forktail Blue Eye Rainbowfish

Forktail Blue Eye Rainbowfish are relatively easy to breed in the right setup.

• Egg scatterers (prefer moss or spawning mops)
• Males display to attract females
• Eggs hatch in about 10–14 days

Separate eggs or fry if you want higher survival rates.

Size & Lifespan

• Adult size: ~2 inches
• Lifespan: 2–3 years with proper care

Common Mistakes to Avoid

• Keeping them in groups that are too small
• Poor water quality or infrequent water changes
• Overfeeding
• Housing with aggressive tank mates

Forktail Blue Eye Rainbowfish vs Other Nano Fish

When choosing the right fish for your aquarium, it helps to compare the Forktail Blue Eye Rainbowfish (Pseudomugil furcatus) to other popular nano species. While many small fish look great in planted tanks, Forktails stand out for their color, activity level, and peaceful nature.

Forktail Blue Eye Rainbowfish vs Neon Tetras

• Forktail Rainbowfish: More active, constantly swimming in mid-to-upper levels
• Neon Tetras: Slower, tend to stay mid-to-lower levels
• Color: Forktails offer bright yellow fins and blue eyes, while Neons have the classic blue/red stripe
  Best choice if you want more movement and energy in your tank

Forktail Blue Eye Rainbowfish vs Endlers Livebearers

• Forktail Rainbowfish: Egg scatterers, require groups for best behavior
• Endlers: Livebearers that reproduce quickly
• Care level: Both are beginner-friendly, but Endlers can overpopulate fast
  Best choice if you want a controlled population and schooling behavior

Forktail Blue Eye Rainbowfish vs Chili Rasboras

• Forktail Rainbowfish: Larger (~2 inches) and more active swimmers
• Chili Rasboras: Much smaller (~1 inch), more shy and subtle
• Visibility: Forktails are more noticeable in most tanks
  Best choice if you want a more visible, active centerpiece fish

Which One Should You Choose?

If you’re looking for a peaceful, colorful, and highly active nano fish, Forktail Blue Eye Rainbowfish are one of the best all-around options. They combine the vibrancy of tetras, the ease of care of Endlers, and better visibility than ultra-small species like Chili Rasboras.

How big do Forktail Blue-Eye Rainbowfish get?

Forktail Blue-Eye Rainbowfish will reach about 2.5 inches. 

How many Forktail Blue-Eye Rainbowfish can I keep per gallon?

We recommend keeping at least 6 Forktail Blue-Eye Rainbowfishand up to 20 is even better. We recommend at least a 10g tank and ideally a 20g.  So, at a minimum of 6 fish per 10 gallon tank or about 2 fish per gallon.  

How long do Forktail Blue-Eye Rainbowfish live?

2-3 years is the average lifespan of a Forktail Blue-Eye Rainbowfish. 

Are Forktail Blue-Eye Rainbowfish easy to Breed?

Breeding Forktail Blue-Eye Rainbowfish is fairly easy. These fish will breed as long as they are not too old (>2 years) and the water is not too cold (>78 F).  You’ll have a higher chance of preserving Rainbowfish fry if you remove the adults after they’ve spawned.

What is the diet of Forktail Blue-Eye Rainbowfish?

Forktail Blue-Eye Rainbowfish do best with an omnivorous diet.  This consists of high-quality flake, freeze-dried and frozen foods, both meaty and plant-based.

What are the best tankmates for Forktail Blue-Eye Rainbowfish?

Forktail Blue-Eye Rainbowfish typically are incredibly peaceful fish and get along with other fish AND shrimp.  We recommend keeping forktail blue-eye rainbowfish in large numbers (20+ is ideal) because they are known to thrive when schooling together.

Feel free to add shrimp, crayfish, snails, and other peaceful fish to your tank with them.  They also LOVE planted tanks due to extra nutrients and hiding places.

What is the best way to Acclimate my new Forktail Blue-Eye Rainbowfish?

When adding new tankmates to your already existing tank, it is important to take the proper steps in introducing and acclimating them into their new home. The whole process is extremely stressful for the fish. Acclimation is important for fish as it allows them time to adjust to the temperature and parameters of their new environment. By doing this correctly, you will reduce the chances of shock or death of your new crayfish. We recommend drip acclimation for fish as it is generally the best option to adjust them slowly to your tank.  You can find our Premium Drip Acclimation Kit here. 

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