Max Size: 2cm

Fire Ant Tetra (Hyphessobrycon myrmex)

The Fire Ant Tetra is a relatively new species, only discovered in 2017. These Tetras are a truly unique South American characin that exhibits sexual dichromatism.

Fire Ant Tetras may be kept in a community aquarium; however, due to their small size and timid nature, you should only keep them alongside other small, small Characins.

Fire Ant Tetras are a schooling species in nature; therefore, it would be best to keep these fish in a group of 10 or more individuals for their comfort and overall appearance. In addition, keeping these Tetras in more significant numbers will give your aquarium a more natural-looking display.

Fire Ant Tetras can be kept in either a heavily planted nano aquarium or a standard South American river biotope setup. The aquarium should have a sandy substrate, dense planting, leaf litter and driftwood branches and roots placed in a way that will form many shady spots. Floating plants will also help subdue the light to make them feel less nervous.

The males of the Fire Ant Tetras have a reddish-orange body colour that becomes less intense towards the dorsal fin. The male's head is mostly red with silver pigmentation and an orange Jaw.

The dorsal portion of their eye is intensely orange, and the anterior margin is light orange, and the posterior margin is silver. All their fins are intensely orange to red, except for the dorsal fin, which is hyaline, with a few orange specs at the base of the last three to four branched dorsal-fin rays.

In contrast, the females and the juvenile Fire Ant Tetras bodies are a pale yellow colour. The female's head is also pale yellow, and their jaw is a light yellow. Their eyes are silvery with a yellowy-orange pigmentation. The adipose and dorsal fins are light yellow, and the remaining fins are pale orange.

Both male and female Fire Ant Tetras exhibit a dark lateral stripe down their sides and above their caudal fins.

Quick Facts
Scientific NameHyphessobrycon myrmex
Other NamesAnt Tetra
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 8+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH6.0 - 7.5
GH5 - 15
TDS36 - 179
72 - 82℉
22.2 - 27.8℃


Fire Ant Tetra

Natural Habitat

Fire Ant Tetras are endemic to the Formiga River, a tributary of the Juruena River in Serra dos Parecis as well as the upper Rio Tapajós basin in Mato Grosso State in Brazil in South America. They inhabit very fast flowing crystal-clear waters with a substrate consisting of sand, stones, and a reasonable amount of vegetal debris.


In the aquarium, Fire Ant Tetras are not particularly fussy eaters. Therefore, it would be best to provide them with good quality dried food such as flakes or granules as the staple diet. It would also be beneficial to occasionally give them live, frozen or freeze-dried foods such as brine shrimp, daphnia, mosquito larvae and bloodworm as a treat. Variety is the key to keeping your fish healthy and will bring out their best colours.

Sexual Dimorphism

It is super easy to differentiate between male and female Fire Ant Tetras. Adult males are usually darker and more brightly coloured than females. In addition, the adult males anal fin is straight to slightly concave, whereas the female's anal fin is always concave. In contrast, the females are usually much lighter and not as vibrantly coloured as males.


Unfortunately, there is not much information on breeding Fire Ant Tetras. However, these Tetras will more than likely breed similarly to other Hyphessobrycon species.

Fire Ant Tetras are egg-scattering free spawners that exhibit no parental care. Adult fish in good condition may spawn in a community tank, and small numbers of fry may start to appear without intervening.

However, If you want to raise a decent number of fry, you will require a separate breeding tank. The tank should be dimly lit, and the base needs to have some mesh or bundles of fine-leaved plants like java moss; this will protect the eggs from the adults.

Their water should be soft, slightly acidic to neutral, and the temperature needs to be between 79 and 82 degrees Fahrenheit. You will also need to provide very gentle filtration through an air-driven sponge filter, and dedicated lighting will not be required as eggs and fry can be a little sensitive to light.

You can breed Fire Ant Tetras in pairs or small groups; however, make sure you remove the adults after spawning; otherwise, they may consume the eggs if given a chance.

Once the eggs have hatched, the babies will firstly feed on their yolk sacs for a short period. Once the babies become free-swimming, you will need to provide them with microscopic foods such as infusoria and Paramecium. You should then offer them microworm or baby brine shrimp as they develop.

Other Tetras of interest

African Moon Tetra(Bathyaethiops caudomaculatus)
African Red Eyed Tetra(Arnoldichthys spilopterus)
Black Darter Tetra(Poecilocharax weitzmani)
Black Line Tetra(Hyphessobrycon scholzei)
Black Neon Tetra(Hyphessobrycon herbertaxelrodi)
Black Phantom Tetra(Hyphessobrycon megalopterus)
View all Tetras
Date Added: 15/11/2021 12:53:14 - Updated: 04/01/2022 16:50:55