Max Size: 4cm

Rainbow Tetra (Nematobrycon lacortei)

The Rainbow Tetra is uncommon and rare in the hobby, but they are a beautiful, hardy, and a peaceful shoaling species. Still, they can be somewhat territorial and may bully other fish. Yet, as long as you have a group of 8 or more they can happily be kept with other species in the community aquarium.

On its club-shaped body, this fish is iridescent and displays every colour of the Rainbow. It also displays a dark line extending from its eye to its caudal fin. There are also elongated anal fins extending from the fish's vent to the caudal fin and a trident-tailed caudal fin with a central spike. Moreover, Rainbow Tetras have large, red-banded eyes.


Rainbow Tetras
Rainbow Tetra
Rainbow Tetras
Rainbow Tetra
Rainbow Tetra
Rainbow Tetra
Rainbow Tetra
Rainbow Tetras
Quick Facts
Scientific NameNematobrycon lacortei
Year Described1971
Aquarium LevelMiddle
DifficultyBeginner - Intermediate
Best kept asGroups 8+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH5.0 - 7.0
GH5 - 8
72 - 80℉
22.2 - 26.7℃


In the home aquarium, the Rainbow Tetra will readily accept most good quality dried foods such as granules, flakes and sinking pellets. These modern food products have been developed to provide all adequate nutrition to maintain your fish's health and dietary requirements.

Providing additional foodstuffs such as live, frozen, and freeze-dried meals such as bloodworm, daphnia, and tubifex once or twice a week will provide additional benefits to your fish's health and well-being but is not a must for this fish.

It should be noted that bloodworms should only be given as an occasional treat and should not be used as the staple diet as they are difficult for fish to digest and can potentially cause blockages.

This fish is an omnivore in the wild, meaning it will consume some vegetable matter. Although most modern fish foods take this into account and include them in their products, you can still supplement your fish's diet with blanched vegetables such as spinach, broccoli, and zucchini. Ensure you do not overfeed your fish and remove any leftovers the following day.

Sexual Dimorphism

It is effortless to determine the male species from the females.

Adult males have more-extended anal, dorsal and caudal fins are much more colourful, and they possess red eyes, whereas the females have green-blue eyes and are much more full-bodied than the males mostly when ready to spawn.

Other Tetras of interest

Adonis Tetra(Lepidarchus adonis)
African Moon Tetra(Bathyaethiops caudomaculatus)
African Red Eyed Tetra(Arnoldichthys spilopterus)
Arowana Tetra(Gnathocharax steindachneri)
Black Darter Tetra(Poecilocharax weitzmani)
Black Line Tetra(Hyphessobrycon scholzei)
View all Tetras
Date Added: 09/09/2020 - Updated: 12/10/2022 12:32:22