Ruby tetra

Care at a glance

Overview

Keep ruby tetras in a group of at least 8 to 10, since a lone fish or a tiny group will hide and lose color. They show their deepest red over dark substrate in soft, tannin stained water. Pair them only with other tiny, gentle fish, as they are easily outcompeted at feeding time.

In the wild

Lives in slow, shaded blackwater creeks and forest streams stained brown by tannins. The water is soft, acidic, and often shallow, with leaf litter and submerged wood on the bottom. These little tetras hang in loose groups among roots and overhanging plants.

Good to know

Axelrodia riesei is one of the smallest characins in the hobby, with adults barely reaching 2 cm. Its warm red body carries a small dark spot at the base of the tail. The genus name honors the tropical fish author Herbert Axelrod.

Did you know

The whole body glows a deeper ruby red when the water is soft and acidic, which is why keepers add botanicals and leaf litter to bring out the color.

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