Pacific Blue Eye Care Guide - Aquarium Setup, Diet & Breeding

The Pacific Blue Eye is a small, lively rainbowfish relative recognised for its striking blue eyes and delicate, translucent body. Depending on locality and mood, the body may show silvery, olive or golden tones, while the fins can carry yellow, orange or reddish highlights. Males are especially attractive when displaying, with larger fins and stronger colouration than females.

These fish are active midwater swimmers that spend much of their time moving through open water and investigating their surroundings. Males may face one another and flare their fins in harmless displays, particularly when competing for the attention of females.

Across its natural range, Pseudomugil signifer occurs in habitats that vary considerably, from flowing coastal creeks and rainforest streams to sluggish waterways, billabongs and estuaries. This adaptability has helped make it one of the most widespread blue-eyes in Australia.

The species is part of the Pseudomugilidae family, a group of small fishes noted for their brilliant eyes, energetic behaviour and distinctive fin displays. Wild populations can differ noticeably in colour and pattern according to their locality, so responsibly sourced specimens are preferable where available.

Pacific Blue Eyes are native to coastal eastern Australia, from southern Queensland through New South Wales and into eastern Victoria. They inhabit a wide range of clear and tannin-stained streams, coastal wetlands, lagoons and estuarine waters, including areas influenced by brackish conditions.

A group of Pacific Blue Eyes should be given at least a 60-litre aquarium, with a footprint of roughly 60 by 30 cm or larger. Use gentle filtration with some water movement, leave open swimming space through the middle and provide dense planting around the sides and back. Fine-leaved plants, moss or floating vegetation offer useful cover and spawning sites, while a dark sand or fine-gravel substrate helps their colours stand out. A secure lid is recommended because these active fish can jump.

Males reach up to about 5 cm (2 inches), while females are usually slightly smaller at around 4–4.5 cm (1.6–1.8 inches).

Pacific Blue Eyes are small omnivores that naturally feed on tiny aquatic invertebrates, insect larvae, crustaceans and algae or other plant material. Offer a varied diet of quality crushed flakes or fine micro-pellets supplemented with newly hatched brine shrimp, daphnia, cyclops and other suitably sized frozen or live foods. Small portions offered regularly help ensure that all members of the group get enough to eat.

Pacific Blue Eyes are peaceful community fish and can be kept with other similarly sized, non-aggressive species. Suitable companions include small Australian rainbowfish, other peaceful blue-eyes, small rasboras, peaceful tetras, white cloud mountain minnows, small Corydoras and gentle livebearers. Avoid large or predatory fish, fin-nippers and boisterous species that may intimidate them or outcompete them for food. They should also not be housed with aggressive cichlids or fish large enough to swallow them.

Pacific Blue Eyes are egg scatterers that readily spawn among fine-leaved plants, moss or a spawning mop. A breeding group can be conditioned with small live or frozen foods, after which females deposit a few adhesive eggs each day and males fertilise them. Remove the spawning material or eggs to a separate container, as the adults may eat them. Eggs generally hatch in around 10–14 days, and the tiny fry need infusoria or other suitably small first foods before progressing to newly hatched brine shrimp.

Males are generally larger and more vividly coloured than females, with longer, broader fins and more pronounced fin extensions. Females have a rounder body profile and shorter, less ornate fins.