TankBud

Neon blue-eye

Pseudomugil cyanodorsalis

Also known as Blueback blue-eye

BrackishFish

Neon blue-eye (Pseudomugil cyanodorsalis)
Andrewbogott · CC BY-SA 4.0

Care at a glance

Temperature
72–82°F
22–28°C
pH
7.0–8.5
Adult size
1.4 in
3.5 cm
Minimum tank
12 gal
45 L
Temperament
Peaceful
Social behavior
Schooling
Swim level
Middle
Diet
Carnivore
Difficulty
Medium
Breeding
Egg scatterer · Medium
Rarity
Common
Family
Pseudomugilidae
Origin
Coastal northern Australia (WA, NT, Queensland), possibly southern New Guinea

Overview

The neon blue-eye is a timid little schooling fish for a mature brackish tank. It is best for a keeper with a little experience.

Did you know

Neon blue-eyes live in brackish water in the wild, and they color up best there. Yet opinions split on whether they actually need salt, since wild-collected stock can adapt to pure freshwater and even breed in it.

Caring for the neon blue-eye

Keep neon blue-eyes in a colony of 8 to 10 or more, in a tank of at least 12 gal (45 L). Add them only to a mature, well-planted tank, since a fresh setup is the fastest way to lose such a small fish. Give them steady flow and good oxygenation. They are strong jumpers, so keep a tight cover on the tank.

Hold the water warm and brackish, at 72 to 82°F (22 to 28°C) and a pH of 7.0 to 8.5. Roughly 1 teaspoon of marine salt per 10 liters makes it brackish. Feed small live or frozen foods like daphnia, moina, baby brine shrimp and microworm.

Neon blue-eyes are peaceful but timid middle swimmers that get outcompeted easily. Keep them only with small, gentle, salt-tolerant species. The males show their best color when competing for attention.

They are egg scatterers with no parental care. Breeders raise the eggs on spawning mops in a dedicated tank. Breeding them is rated medium.

Good to know

The neon blue-eye is a tiny rainbowfish in the family Pseudomugilidae. It is euryhaline, meaning it handles a wide range of salinity, up to about 25 to 50 percent seawater. It is also called the blueback blue-eye.

In the wild

Neon blue-eyes come from coastal northern Australia, across Western Australia, the Northern Territory and Queensland, and possibly southern New Guinea. They live in tidal creeks and mangrove edges, in warm, salty backwaters where fresh and sea water meet.

Common questions

What size tank does a neon blue-eye need?

A neon blue-eye needs at least 12 gal (45 L). It spends most of its time in the middle.

What temperature and pH does a neon blue-eye need?

A neon blue-eye is comfortable at 72–82°F (22–28°C) with a pH of 7.0–8.5.

What does a neon blue-eye eat?

A neon blue-eye eats small live or frozen foods like daphnia, moina, baby brine shrimp and microworm.

How big does a neon blue-eye get?

An adult neon blue-eye reaches about 1.4 in (3.5 cm).

Does a neon blue-eye need a group?

Yes. A neon blue-eye is a schooling species and should be kept in a group, not singly.

How does a neon blue-eye breed?

Neon blue-eyes are egg scatterers and give no parental care. Breeders raise the eggs on spawning mops in a dedicated tank.

Related species