All fish / Characidae

Rainbow Tetra

Nematobrycon lacortei

Also known as rainbow emperor tetra, red-eyed emperor tetra, lacortei tetra, rainbow tetra, lacortei emperor tetra, レインボーテトラ, 彩虹帝王灯, 红眼帝王灯

No free-to-use photo of this fish yet. Took one yourself? Send it to us and we will credit you.

A close relative of the emperor tetra, it has an iridescent body that shifts between green, violet and pink, a dark side stripe and bright red eyes in males. Males also have a three-pointed tail with an extended centre ray. It is kept for its subtle rainbow sheen and calm nature in planted community tanks.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

5 cm

Temperature

23 to 27 °C

pH

5.5 to 7.5

Smallest tank

80 litres

Keep as

Group of 6 or more, ideally more females than males

Diet

Omnivore: quality flakes and granules plus live or frozen bloodworm, daphnia and brine shrimp

Swims

Middle of the tank

Lifespan

3 to 5 years

Water

Freshwater

Wild range

Colombia (San Juan and Atrato river basins, Pacific slope)

Breeding

It scatters eggs among fine-leaved plants or mops and gives no parental care. Spawning is quite achievable in soft, slightly acidic water, though the adults will eat eggs and the fry are small and need infusoria at first.

Good to know

Males can squabble among themselves, so give plenty of plants and keep more females. It is easily confused with Nematobrycon palmeri, which has a blue-green body and greenish rather than red eyes in males.