Pacific Blue-eye

The Pacific blue-eye is an extremely adaptable species that lives over a very wide area along the east coast of Australia, from north to south. The males' long first dorsal fin and yellow second dorsal and anal fins edged in black and white form a pleasing contrast with their plain bodies. It grows to 4–5 cm.

In the wild it can be found in waters ranging from fresh to brackish, even in estuaries by the sea; this flexibility also makes it hardy in the aquarium. Because of its wide distribution, there are differences in color and size between populations. It is short-lived, living 2–3 years.

It lives in the coastal rivers of eastern Australia, in planted streams, ponds, along mangrove edges and in estuaries. Southern populations are exposed to quite cool water in winter. The fish usually move close to the shore, among plants and roots, in water near the surface.

• Volume: at least 60 liters and 60 cm in length for a school of 6–10.
• Water: 22–26°C, neutral to slightly alkaline, moderately hard water. It also adapts to water with a small amount of added salt, but lives without problems in fresh water.
• Plants: Dense plants and floating plants, with open swimming space in the middle.
• Flow: Gentle flow is enough.
• Lid: It can jump; use a lid.

Omnivorous. It accepts fine flakes and micro granules; vary the diet with frozen and live brine shrimp, cyclops, daphnia and small bloodworms. It takes food mostly from the surface. Feed small amounts 2–3 times a day.

Peaceful and active. Males often spread their fins and display to each other and may claim small territories; the chasing is usually harmless. It gets along well with shrimp and may eat only very small young.

Good companions: Neocaridina shrimp, otocinclus, corydoras, small rasboras, McCulloch's and neon dwarf rainbowfish, nerite snails.

Avoid: large and fast fish, fin nippers, aggressive species; if you plan to breed, other Pseudomugil species.

At least 6, ideally 10 or more individuals. Because displays and chasing between males can be intense, set up a group with 2 females per male; a layout broken up by plants prevents a single individual from being constantly targeted.

An easy-breeding egg scatterer. Females lay a few eggs every day on fine-leaved plants or a wool spawning mop; the eggs attach with sticky threads. Because the parents may eat the eggs, move the mop to a separate container. Depending on temperature, the fry hatch in about 10–20 days; they are fed micro food, infusoria and, soon after, newly hatched brine shrimp.

Hybridization: It can hybridize with other Pseudomugil species. Do not mix different populations either; pass on the fry with information on their origin.

• Short lifespan: losing fish at 2–3 years old is natural; renew the group with fry.
• White spot and velvet: can appear after transport; quarantine new fish.
• Water quality: fin rot can appear in dirty, stagnant water.
• It is a hardy species that adapts to a wide range of conditions.

Males have a long, prominent first dorsal fin; their second dorsal and anal fins are elongated, yellow and edged in black and white. Females are smaller and plainer; their bodies are silvery-olive, and their fins are short and colorless.