Spotted Blue Eye Rainbowfish

Spotted Blue Eye Rainbowfish Care Guide

Common Names: Spotted Blue Eye Rainbowfish, Gertrude’s Spotted Blue-Eye
Scientific Name: Pseudomugil gertrudae
Origin: Northern Australia, New Guinea, and nearby islands
Size: 2.5–3 cm
Lifespan: 2–3 years
Temperament: Peaceful, active, social
Difficulty: Moderate (due to sensitivity to water changes)

✅ Tank Requirements

• Minimum Tank Size: 40 liters (for a small group)

• Temperature: 22–28°C

• pH: 6.0–7.5

• Hardness: Soft to moderately hard water

• Lighting: Moderate to high (to show off their color)

• Substrate: Dark sand or fine gravel preferred

• Aquascape: Heavily planted with open swimming areas, floating plants help diffuse light

These fish love planted nano tanks and show best coloration in well-maintained, mature aquariums.

‍‍ Social Behavior and Tank Mates

• Schooling fish – always keep at least 6–8 (preferably more)

• Males display beautiful courtship dances and flashing colors when females are present

• Peaceful and suitable for nano tanks

Good tank mates:

• Other peaceful nano species (like chili rasboras, ember tetras, endlers)

• Dwarf corydoras (e.g., pygmy corys)

• Freshwater shrimp (like Neocaridina or Amano)

• Otocinclus catfish

Avoid: Aggressive or fast fish that may nip or stress them (e.g., barbs, bettas)

️ Diet

They are micro-predators and prefer small, live or prepared foods.

Recommended foods:

• Baby brine shrimp (live or frozen)

• Daphnia, microworms

• High-quality micro-pellets or crushed flakes

• Softened blanched veggies (occasionally)

Feed small amounts 1–2 times daily. Their mouths are tiny, so food size matters!

Breeding

Breeding Pseudomugil gertrudae is relatively easy:

• Provide fine-leaved plants or spawning mops

• Males will display and chase females

• Eggs are adhesive and laid one at a time daily

• Remove adults or eggs to prevent them from being eaten

• Eggs hatch in about 7–10 days, fry can be fed infusoria or powdered fry food

Interesting Fact

Despite their tiny size, male Spotted Blue Eye Rainbowfish put on one of the most elaborate mating displays among nano fish. They flare their fins, shimmer with blue and yellow flashes, and perform zig-zag dances to impress females—like underwater fireworks in miniature form!

PLEASE NOTE:

All pictures shown are for illustration purpose only. Actual fish may vary depending on size and variety of species.