Spotted Blue Eye Rainbowfish Care Guide – Aquarium Setup, Diet & Breeding

Spotted Blue Eye Rainbowfish are tiny, elegant freshwater fish with translucent bodies marked by dark spots and iridescent blue eyes. Their fins can show yellow, orange, red or black edging, with males usually displaying the strongest colour and the most elaborate fin patterning.

They are active but peaceful fish that spend much of their time in the middle and upper areas of the aquarium. A group creates an appealing display as males posture, spread their fins and perform short courtship dances without causing serious harm to one another.

In the wild, they live in quiet, plant-rich waters where dappled light, leaf litter and submerged vegetation provide cover. Their small size and delicate movements reflect life in sheltered habitats rather than fast-flowing rivers.

The species is part of the Pseudomugilidae family, a group of small blue-eyes found around Australia and New Guinea. Although they are sometimes called rainbowfish, they are distinct from the larger Melanotaenia rainbowfish commonly kept in community aquariums.

Spotted Blue Eye Rainbowfish are native to northern Australia and southern New Guinea, including the Trans-Fly region and nearby islands. They inhabit shallow, slow-moving or still waters such as swamps, forest pools, creeks and drainage channels, often surrounded by dense vegetation.

A group should be kept in an aquarium of at least 40 litres, with a footprint of around 60 × 30 cm providing useful swimming length. Use a secure lid because these active fish may jump, and include dense plants, fine-leaved vegetation, floating cover, driftwood and subdued lighting to recreate a sheltered shallow-water habitat. A dark, fine-grained substrate helps their colours stand out, while open water should remain available for group swimming. Gentle filtration and modest water movement are preferable to a strong current.

Up to about 4 cm (1.6 in) overall; males are generally larger and more robust than females, which usually reach around 3–3.5 cm (1.2–1.4 in).

Offer a varied diet of appropriately sized crushed flakes, fine granules and small frozen foods such as cyclops, daphnia and baby brine shrimp. Live foods are particularly useful for bringing out their colour and encouraging spawning. Their small mouths require food particles that are easy to swallow, and several modest feedings are preferable to one large meal.

Spotted Blue Eye Rainbowfish suit peaceful nano-community aquariums. Suitable companions include small rasboras, ember tetras, pencilfish, peaceful dwarf corydoras, Otocinclus and other similarly sized, calm fish. They can also be kept with peaceful freshwater shrimp, although very small shrimp and shrimplets may be eaten. Avoid large, boisterous or fin-nipping species, aggressive fish and fast competitors that may outcompete them for food.

Spotted Blue Eye Rainbowfish are egg scatterers that readily spawn among fine-leaved plants, moss or spawning mops. Condition a group with small live or frozen foods, then remove the spawning material regularly and move it to a separate, gently filtered rearing container. The tiny fry need infusoria or another suitably fine first food before progressing to newly hatched brine shrimp. They can spawn frequently, but adults may eat eggs and young.

Males are typically larger and much more colourful, with broader, longer fins, stronger dark markings and more noticeable red, yellow or orange fin details. Females are smaller, plainer and more rounded through the abdomen, especially when carrying eggs.