Serpae tetra (Hyphessobrycon eques) care guide

Group
Freshwater fish
Other names
Jewel tetra, Red minor tetra, Blood tetra, Callistus tetra, Megalamphodus eques, Blood characin
Family
Acestrorhamphidae (American tetras; formerly Characidae)
Origin
Widespread in South America: the Amazon basin in Brazil, Peru and Bolivia, plus the Guaporé and Rio Paraguay basins in Brazil, Paraguay and Argentina.
Water
freshwater
Maximum size
4 cm
Temperature
20–28°C
pH
5–7.5
Hardness
Soft to medium-hard, 1–15 dGH
Minimum tank
72 litres
Care level
beginner
Temperament
semi_aggressive

Care

The serpae is a hardy, colourful and very common tetra, but it has earned a reputation as a fin nipper. The best way to keep that under control is a big group: Seriously Fish recommends at least 12, so the fish spend their energy squabbling among themselves rather than chasing tankmates. Males form loose pecking orders, which is natural. A tank with a base of at least 80 × 30 cm (around 72 litres) is the minimum. They colour up best in a well-furnished tank with live plants and a dark substrate; a natural look with soft sand, wood roots and branches and some dried leaf litter works well. They are adaptable about water: 20–28 °C, acidic to slightly alkaline (pH 5–7.5) and soft to moderately hard water. Farmed fish, which make up most of the trade, are more adaptable than wild-caught ones. Keep the water clean with regular partial changes. Known for nipping and harassing both its own kind and tankmates, and this aggression reportedly persists even in larger groups or bigger tanks; almost all trade fish are captive-bred. Sources: Seriously Fish (seriouslyfish.com/species/hyphessobrycon-eques/); FishBase (fishbase.se/summary/Hyphessobrycon-eques.html); Wikipedia (en.wikipedia.org/wiki/Serpaetetra). Checked October 2026.

Diet

Omnivorous; in the wild it eats small invertebrates, crustaceans, filamentous algae and fallen fruit. In the aquarium give a good dried food as a staple and add live and frozen foods such as bloodworm, mosquito larvae and Daphnia regularly.

Breeding

An egg-scattering free spawner with no parental care; it often spawns in mature tanks. Females are noticeably rounder and slightly larger than males. For a controlled spawning, set up a small, very dimly lit tank with mature water, slightly acidic to neutral, at the warmer end of the range. Cover the base with mesh, plastic grass matting or glass marbles so eggs fall out of reach, or use fine-leaved plants or spawning mops, and add a gentle air-driven sponge filter. Add a well-conditioned pair, or one or two males with several females, and remove them once eggs appear, usually the next morning. Feed the fry Paramecium or a 5–50 micron dry food, then brine shrimp nauplii and microworm.

Compatibility and tank mates

Best with lively, robust fish of similar or larger size that can hold their own, such as danios, barbs, other boisterous tetras, Corydoras and sturdier catfish. Do not keep with shy, slow-moving or long-finned fish such as bettas, angelfish, fancy guppies or gouramis, especially if the shoal is small or the tank cramped.

Last updated 4 October 2026. Community-edited care guide on Aquatic-Auctions.

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