What tank size does a Serpae Tetra need?

A Serpae Tetra needs an aquarium of at least 75 litres (19.8 US gallons) with a footprint at least 80 cm (31.5 in) long — for this species, swimming length matters as much as raw volume.

What water parameters does a Serpae Tetra need?

Serpae Tetra does best at 20–28 °C (68–82.4 °F), pH 5–7.5 and a general hardness of 1–15 °dGH.

What group size does a Serpae Tetra need?

Serpae Tetra is a social species — keep a group of at least 10 so natural behaviour emerges and stress stays low.

Is the Serpae Tetra suitable for beginners?

Yes — Serpae Tetra is one of the easier species to keep and forgives typical first-tank mistakes, as long as the aquarium is cycled and maintained.

Species library

Serpae Tetra

Hyphessobrycon eques

Characidae

FishDifficulty: ●●○○○Data: well-established

📷 Francesco Loda · CC BY 3.0 · resized · Wikimedia Commons

Serpae Tetra — Hyphessobrycon eques — 📷 Francesco Loda · CC BY 3.0 · resized · Wikimedia Commons

About

The serpae tetra is a small, deep-bodied characin from the still and slow-moving tributaries, backwaters and ponds of the Paraguay and Guaporé river basins in South America. Prized for its intense blood-red body and dark shoulder blotch, it is hardy and adaptable but notoriously nippy, earning a reputation as one of the hobby's most persistent fin-nippers when kept in small groups. Nipping and internal squabbling ease markedly in a large shoal with a spacious, well-planted tank that breaks up sight lines.

Care

Keep in a bold shoal of 10+ (ideally 10-15) in a planted tank of 75 L or more with a base at least 80 cm long for open swimming space. A committed fin-nipper: avoid slow, long-finned tankmates such as bettas, angelfish, guppies and gouramis.

Diet

Micro-predatory omnivore; feed varied dry foods plus regular frozen or live bloodworm, daphnia and mosquito larvae to fuel colour and activity.

Tankmate compatibility

Computed by the AquaSage engine for a spacious reference tank — always check the full verdict for your exact setup in the calculator.

Telling males from females

What works for this species, most reliable first.

Belly depthA hint only · only on well-fed adults, and only as a comparison
For most tetras, barbs and rasboras this is all there is: a conditioned female is deeper through the belly than a male of the same length.

All the methods, with diagrams

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Fish for a 112 litre tank

Frequently asked questions

What tank size does a Serpae Tetra need?: A Serpae Tetra needs an aquarium of at least 75 litres (19.8 US gallons) with a footprint at least 80 cm (31.5 in) long — for this species, swimming length matters as much as raw volume.
What water parameters does a Serpae Tetra need?: Serpae Tetra does best at 20–28 °C (68–82.4 °F), pH 5–7.5 and a general hardness of 1–15 °dGH.
What group size does a Serpae Tetra need?: Serpae Tetra is a social species — keep a group of at least 10 so natural behaviour emerges and stress stays low.
Is the Serpae Tetra suitable for beginners?: Yes — Serpae Tetra is one of the easier species to keep and forgives typical first-tank mistakes, as long as the aquarium is cycled and maintained.

Sources

Water & tank

Temperature20–28°C

Optimal temp.24–26°C

pH5–7.5

Hardness (GH)1–15°d

Carbonate (KH)0–8°d

Adult size4 cm

Min. volume≥ 75 L

Min. tank length≥ 80 cm

Group size≥ 10

Swimming zoneMid

TemperamentSemi-aggressive

Water typeFreshwater

FlowLow

Lifespan~6 yrs

Try in the calculator