Description
Hyphessobrycon myrmex is a diminutive tetra, 2.4 cm, from Brazil, with the lower half of the body heavily pigmented and a diffuse dark stripe along the flank, above all over the anal fin, and dark pigment on the first rays of the dorsal fin. Its name, myrmex, means «ant».
The type locality is a hydroelectric reservoir on the Formiga River, built in 2010; the place is presumed to have resembled the neighbouring stretches before the dam, a narrow, shallow river of clear, fast water over stones, sand and plant debris. It is a small omnivorous schooling fish that needs a small tank with clean water and plants.
Behavior
A peaceful schooling fish that does better in a group of eight or more. Given its size, companions should be calm and small, and the tank should offer plants for shelter.
It lives well with other diminutive tetras, small rasboras and dwarf corydoras.
Avoid housing it with large or lively fish, which intimidate it and take its food.
Habitat
Hyphessobrycon myrmex is known from Brazil; the type locality is a hydroelectric reservoir of about 6.8 km² built in 2010 on the Formiga River. Before the dam, the place would have resembled the stretches upstream and downstream: a narrow river, 10 to 15 m wide and at most 1.8 m deep, with fast water and riffles, clear, with a bottom of stones, sand and a moderate amount of plant debris.
Hyphessobrycon myrmex is a schooling species, which means that in the wild it lives and moves in large, coordinated groups.
Keep at least 8 individuals so they feel comfortable and their stress level stays low.
Details
🌊 Water parameters
🐠 Minimum tank size
Breeding
Its breeding is not documented. Like other small tetras, it probably scatters its eggs among fine-leaved plants without caring for them.
Diet
An omnivore leaning to invertebrates: in the river it eats mostly mayfly nymphs, and also chironomid larvae, microcrustaceans, filamentous algae and plant tissue.
- Staple: quality small flakes and granules.
- Supplement: brine shrimp, daphnia or mosquito larvae, live or frozen.
What about your tank?
Enter your tank's values to see only the compatible species that fit them. Litres apply to fish.
Compatible fish
General guidance based on water parameters, behaviour and known exceptions; always review the individual animals' and aquarium's specific needs.
They share water: pH 6–7 and 24–28 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 23–28 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7 and 23–28 °C.
They share water: pH 6–7 and 23–28 °C.
They share water: pH 7–7.5 and 26–28 °C.
They share water: pH 6–7.5 and 22–25 °C.
They share water: pH 6–7 and 22–28 °C.
They share water: pH 6–7 and 24–26 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6–7 and 24–27 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6.5–7.5 and 24–26 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 22–25 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6.5–7.5 and 22–24 °C.
They share water: pH 6–7 and 27–28 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6.5–7.5 and 22–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7 and 24–28 °C.
They share water: pH 6–7.5 and 26–28 °C.
They share water: pH 6–7 and 23–28 °C.
They share water: pH 6–7.5 and 23–28 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6–7 and 24–28 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6–7 and 22–26 °C.
They share water: pH 6–6.5 and 23–27 °C.
They share water: pH 6.5–7.2 and 22–26 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–7.5 and 22 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6.5–7.5 and 22–24 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7 and 23–28 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–26 °C.
They share water: pH 6–7.2 and 22–28 °C.
They share water: pH 7–7.5 and 22–27 °C.
They share water: pH 7–7.5 and 22–26 °C.
They share water: pH 6–7.2 and 22–26 °C.
They share water: pH 6–7.2 and 24–28 °C.
They share water: pH 6–7.2 and 24–28 °C.
They share water: pH 6–7 and 26–28 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 25–28 °C.
They share water: pH 6–6.5 and 24–28 °C.
They share water: pH 6–7 and 24–28 °C.
They share water: pH 6–7 and 23–28 °C.
They share water: pH 6–7.5 and 23–27 °C.
They share water: pH 6–7.2 and 22–28 °C.
They share water: pH 6–7.5 and 23–28 °C.
They share water: pH 6–7.5 and 24–28 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 23–27 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 6–7.5 and 22–28 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 6–7.5 and 22–27 °C.
They share water: pH 7–7.5 and 22–28 °C.
Compatible invertebrates
General guidance based on water parameters, behaviour and known exceptions; always review the individual animals' and aquarium's specific needs.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6–6.5 and 22–24 °C.
They share water: pH 6.5–7.5 and 22–27 °C.
They share water: pH 7–7.5 and 22–25 °C.
They share water: pH 7.5 and 24–28 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7.5 and 26–28 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6–6.8 and 22–24 °C.
They share water: pH 6–6.8 and 22–24 °C.
They share water: pH 6.5–7.5 and 22–27 °C.
They share water: pH 7.5 and 27–28 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 6.5–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6.5–7.5 and 23–28 °C.
They share water: pH 6.5–7.5 and 23–28 °C.
They share water: pH 7.5 and 27–28 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–7.5 and 23–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6.5–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 7–7.5 and 22–28 °C.
They share water: pH 6–6.5 and 22–24 °C.
Sources
- FishBaseFroese, R. and D. Pauly. Editors. 2026. FishBase. World Wide Web electronic publication.
There is no source for this species' water: none of the accepted sources records its pH, temperature or hardness, and the profile's ranges are estimated from its congeners or species of the same genus.
Water: the profile's ranges (pH 6-7.5, 2-12 dGH and 22-28 °C) are estimated from those of other Hyphessobrycon in the catalogue, of the same genus. Size: 2.4 cm SL. Diet and habitat: the data come from the stomach-content study at the type locality that FishBase records, the Formiga River, in Brazil.
Litres per fish, tank sizes and lifespan: the profile's own judgement. The sources consulted do not give them.
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