Redfin glass tetra

Erythrocharax altipinnis

Also known as Altipinnis tetra, Unicorn tetra

FreshwaterFish

Care at a glance

Temperature: 75–82°F (24–28°C)
pH: 5.0–6.8
Adult size: 1.3 in (3.3 cm)
Minimum tank: 14 gal (54 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: No record
Rarity: Rare
Origin: Rio Curuá, Serra do Cachimbo, Brazil
Family: Characidae

Overview

The redfin glass tetra is a tiny, peaceful schooling fish that looks best in a group of at least ten in a soft, gently stained tank. It swims in the middle of the water and shares its home stream with the green-eye tetra, so the two make a natural single-river display. Keep it only with small, calm companions such as other nano tetras, pygmy corydoras, and small rasboras, since larger fish will eat or outcompete it. Feed very small foods: fine flake, crushed micro pellets, cyclops, microworm, and baby brine shrimp. A group is comfortable in around 54 liters or more, well planted and calm.

In the wild

Erythrocharax altipinnis comes from the clear rio Curua, a tributary of the rio Iriri in the upper Rio Xingu basin, draining the Serra do Cachimbo in Para, Brazil, the same plateau streams that hold the green-eye tetra. These waters are warm, soft, and acidic. Keep it from 24 to 28 degrees Celsius at pH 5.0 to 6.8 with low hardness, using driftwood, leaf litter, a dark substrate, and dim light.

Good to know

Erythrocharax altipinnis was described in 2013 as both a new species and a new genus of the characin family Characidae, and it stays around 3.3 centimeters. The genus name means red charax, for the bright red adipose and tail fins of living fish, while altipinnis refers to the tall dorsal-fin rays that males extend. It is an egg-scattering miniature, and its aquarium breeding is not documented.

Did you know

This one small fish from a single plateau river was different enough that scientists built an entirely new genus around it in 2013, a mark of how isolated and distinct the Serra do Cachimbo streams are.