TankBud

True penguin tetra

Thayeria obliqua

Also known as Short-striped penguin, Obliqua penguin

FreshwaterFish

True penguin tetra (Thayeria obliqua)
The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature
73–82°F
23–28°C
pH
5.5–7.2
Adult size
3 in
7.6 cm
Minimum tank
29 gal
110 L
Temperament
Peaceful
Social behavior
Schooling
Swim level
Middle
Difficulty
Easy
Breeding
No record
Rarity
Rare
Family
Characidae
Origin
Madeira and Guaporé basins, Brazil and Bolivia

Overview

The true penguin tetra is a hardy schooling fish for a peaceful community tank, and it is easy to keep. It swims with its tail held down at an angle, a natural posture and not a sign of illness.

Did you know

The true penguin tetra carried the penguin name first, back in 1908. Almost every penguin tetra in shops is actually Thayeria boehlkei, a look-alike. The original is now the rarer of the two in the trade.

Caring for the true penguin tetra

Keep true penguin tetras in a group of at least eight, in a tank of 29 gal (110 L) or more. They grow larger than most tetras and stay on the move, so give them open swimming room. A darker setup with driftwood, some plants and open surface space brings out their color and their steady, angled swimming.

Give them warm water at 73 to 82°F (23 to 28°C) and a pH of 5.5 to 7.2. Softer, gently acidic water suits them best. Feed a varied diet of flake, small pellets and frozen foods such as bloodworm and daphnia.

True penguin tetras are peaceful and sit in the middle of the tank. They mix well in a community with other calm fish of similar size, and the whole school leans and drifts together. Captive breeding is not well documented.

Good to know

The true penguin tetra is a characin of the family Characidae and the type species of its genus. It is told from the common penguin tetra, Thayeria boehlkei, by its black stripe. That stripe starts around the middle of the body and fades out before the dorsal fin. On the common fish, the stripe runs the full length from gill to tail.

In the wild

Thayeria obliqua comes from the Madeira and Guaporé river basins of Brazil and Bolivia. It lives in warm, slow to moderate forest waters stained with tannins.

Weekly picks

Tank mates

The true penguin tetra is a peaceful, schooling species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a true penguin tetra need?

A true penguin tetra needs at least 29 gal (110 L). It spends most of its time in the middle.

What temperature and pH does a true penguin tetra need?

A true penguin tetra is comfortable at 73–82°F (23–28°C) with a pH of 5.5–7.2.

What does a true penguin tetra eat?

A true penguin tetra eats a varied diet of flake and small pellets. Add frozen foods such as bloodworm and daphnia.

How big does a true penguin tetra get?

An adult true penguin tetra reaches about 3 in (7.6 cm).

Does a true penguin tetra need a group?

Yes. A true penguin tetra is a schooling species and should be kept in a group, not singly.

Related species