Description
The serpae tetra is an intense red characin with a black spot behind the gills and a black dorsal fin edged in white. In a large group over green plants it is one of the most striking fish you can keep for little money.
It does, however, have a well-earned reputation as a fin nipper. It is not aggressive in the sense of fighting, but it pecks at any long fins that cross its path. With a large shoal most of that energy stays within the group.
It is hardy and copes with a wide range of water. The red depends on diet and calm: stressed or poorly fed, it stays a dull pink.
Behavior
Active and shoaling: eight or more. Constant chasing goes on among them without escalating.
It lives well with fast, short-finned fish: black tetras, danios, barbs, corydoras and bristlenose.
Avoid housing it with bettas, gouramis, angelfish, male guppies and any slow or long-finned fish. Adult shrimp are usually fine, but shrimplets do not survive.
Habitat
Hyphessobrycon eques is widely distributed in South America: the Paraguay basin, the Guaporé and parts of the Amazon. It lives in slow water and backwaters with plenty of vegetation, submerged branches and floating plants.
In the aquarium it does well with dense planting at the edges, some roots and a dark substrate, which is where the red shows best.
Tetra serpae 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.
Habitats
Fish sharing this habitat
These fish appear in one or more habitats linked to this profile. It doesn't mean they are directly compatible in an aquarium.
Details
🌊 Water parameters
🐠 Minimum tank size
Breeding
An egg scatterer that spawns among fine plants. Like other tetras it eats the spawn: to breed it, set up a separate soft-water tank and remove the parents as soon as they finish.
The fry start on infusoria and take brine shrimp nauplii after a few days.
Diet
An undemanding omnivore.
- Staple: quality flake or micropellets.
- Colour: foods with astaxanthin or krill to keep the red.
- Supplement: frozen daphnia, brine shrimp and mosquito larvae.
A well-fed serpae nips fewer fins: as with the black tetra, some of the pecking is hunger.
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 6–7.5 and 24–27 °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 22–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 5.5–7 and 22–27 °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 6.5–7.5 and 22–24 °C.
They share water: pH 5.5–7 and 27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–7.5 and 22–27 °C.
They share water: pH 6.5–7.5 and 22–27 °C.
They share water: pH 6–7.5 and 25–27 °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 24–27 °C.
They share water: pH 6–7.5 and 24–27 °C.
They share water: pH 7.5 and 24–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7.5 and 24–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 5.5–7 and 22–26 °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 6–7.5 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 7–7.5 and 22–27 °C.
They share water: pH 5.5–7 and 26–27 °C.
They share water: pH 5.5–7 and 22–26 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 5.5–6.5 and 24–27 °C.
They share water: pH 5.5–7 and 23–27 °C.
They share water: pH 5.5–7.5 and 23–27 °C.
They share water: pH 6–7.5 and 22–26 °C.
They share water: pH 5.5–7.5 and 23–27 °C.
They share water: pH 7–7.5 and 22–27 °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 22–27 °C.
They share water: pH 5.5–6.5 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 24–27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–7.5 and 22–27 °C.
They share water: pH 7–7.5 and 22–27 °C.
They share water: pH 6.5–7.5 and 22–26 °C.
They share water: pH 5.8–6.8 and 22–24 °C.
They share water: pH 5.8–6.8 and 22–24 °C.
They share water: pH 6.5–7.5 and 22–27 °C.
They share water: pH 7.5 and 27 °C. They only meet at the very edge, so the tank has to hold that value.
They share water: pH 7–7.5 and 22–27 °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 22–27 °C.
They share water: pH 6.5–7.5 and 22–27 °C.
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They share water: pH 7–7.5 and 22–27 °C.
Sources
- FishBaseFroese, R. and D. Pauly. Editors. 2026. FishBase. World Wide Web electronic publication.
- Seriously FishSeriously Fish. Hyphessobrycon eques. Ficha de especie; consultada 2026-08.
Both sources now list it as Megalamphodus eques. Hardness: Seriously Fish gives 1-15 and FishBase 10-25 dH.
Plan your next aquarium
Is this fish right for you? Plan a suitable aquarium before setting it up.