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Fish

Spotted blue-eye

Pseudomugil gertrudae
French name : Pseudomugil de Gertrude

The spotted blue-eye is a jewel-like nano fish from soft, tannin-stained swamps, lily lagoons, and slow streams of northern Australia and New Guinea. Barely 3.5 cm, males display large spotted, fan-like fins that they flare in constant sparring displays that never turn harmful. It is peaceful and best kept as a shoal of at least eight, where males color up and compete; it suits a planted blackwater nano tank with subdued light and fine-leaved plants. Provide soft, acidic water (pH 5.0 to 7.0, very low hardness), warm at 24 to 28 C, gently filtered and pristine, ideally with botanicals or peat filtration. Feed small live and frozen foods, cyclops, micro-worms, baby brine shrimp, and fine flakes. Continuous egg-scatterers among mosses and mops. Sensitive to poor water and short-lived.

Water
Freshwater
Origin
Blackwater swamps and streams of northern Australia and southern New Guinea
Adult size
3.5 cm
Diet
Omnivore
Temperament
Peaceful
Difficulty
Intermediate
Keep in group of
8+
Spotted blue-eye (Pseudomugil gertrudae)
Illustration

Water parameters

Temperature24 – 28 °C
pH5 – 7
Carbonate hardness (KH)0 – 4 °dKH
General hardness (GH)1 – 8 °dGH

Tank & stocking

Minimum tank volume40 L
Volume budget per individual 3 L — adds up with tank-mates
Minimum group size8 individuals (shoaling)

“Minimum tank volume” is a reasonable floor, not an absolute limit. The per-individual budget is used by the Aqua app to estimate how heavily a tank is stocked.

Frequently asked questions

What size aquarium does Spotted blue-eye need?

Provide at least 40 litres for a small group to keep Spotted blue-eye in good conditions.

What water parameters does Spotted blue-eye need?

A temperature of 24–28 °C, pH 5–7.

Is Spotted blue-eye peaceful or aggressive?

Its temperament is peaceful.

What does Spotted blue-eye eat?

Its diet: omnivore.

How many Spotted blue-eye should be kept together?

It is a social species: keep a group of at least 8.

How big does Spotted blue-eye get?

Around 3.5 cm as an adult.

Is Spotted blue-eye suitable for beginners?

Care level: intermediate.

Planning a tank with Spotted blue-eye?

AquaTender turns these parameters into live advice: it checks whether your tank is big enough, how heavily it's stocked, and whether your fish are compatible — then tracks water tests, photos and maintenance for you.

➕ Add Spotted blue-eye to my tank Discover AquaTender
« Add to my tank » opens AquaTender — sign in (free) and pick your aquarium.

Fish from the same biotope

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