Pseudomugil gertrudae – Gertrude’s Spotted Blue Eye Rainbowfish

Add brilliant movement and natural beauty to your aquarium with Pseudomugil gertrudae, one of the most eye-catching nano rainbowfish available in the aquarium hobby. Commonly known as the Gertrude’s Spotted Blue Eye Rainbowfish, this peaceful freshwater species is loved for its shimmering blue eyes, delicate finnage, and vibrant spotted patterns.

Native to the slow-moving waters and wetlands of northern Australia and New Guinea, Pseudomugil gertrudae thrives in planted aquariums with gentle flow, dense vegetation, and peaceful tank mates. Their active schooling behavior and constant display activity make them a stunning centerpiece for nano tanks and aquascapes.

These nano rainbowfish are especially popular among planted tank enthusiasts looking for colorful, peaceful fish with unique personality and elegant movement.

Why You’ll Love Pseudomugil gertrudae

• Stunning blue eyes with spotted fins
• Peaceful nano schooling fish
• Perfect for planted aquariums
• Active mid-to-top water swimmer
• Excellent community fish
• Great for nano tanks and aquascapes
• Displays best coloration in groups

Pseudomugil gertrudae Care Guide

Scientific Name

Pseudomugil gertrudae

Common Names

• Gertrude’s Spotted Blue Eye
• Spotted Blue Eye Rainbowfish
• Gertrudae Rainbowfish

Temperament

Peaceful

Adult Size

Approximately 1–1.5 inches

Diet

These omnivorous nano fish readily accept:

• High-quality micro pellets
• Crushed flakes
• Baby brine shrimp
• Daphnia
• Frozen cyclops
• Small live foods

A varied diet helps maximize coloration and breeding behavior.

Water Parameters

• Temperature: 74–82°F
• pH: 6.0–7.5
• Tank Size: 10 gallons or larger
• Water Flow: Gentle to Moderate

Ideal Aquarium Setup

Pseudomugil gertrudae thrive in heavily planted aquariums with:

• Dense aquatic plants
• Floating plants for cover
• Dark substrate
• Open swimming areas
• Stable water conditions

Their colors become especially vibrant under natural-style lighting and planted aquascapes.

For best results, keep them in groups of at least 6–8 individuals to encourage natural schooling behavior and male display activity.

Compatible Tank Mates

Excellent tank mates include:

• Small rasboras
• Corydoras
• Peaceful shrimp
• Kuhli loaches
• Small tetras
• Other nano rainbowfish

Avoid aggressive or fin-nipping fish.

Important Information

Due to their small size, Pseudomugil gertrudae should not be housed with large or aggressive fish. These fish appreciate stable water quality and mature aquariums with plenty of plant cover.

Males will display vibrant finnage and flashing behavior when competing for attention, making them an exciting and active addition to peaceful community tanks.