What tank size does a Diamond Tetra need?

A Diamond Tetra needs an aquarium of at least 75 litres (19.8 US gallons) with a footprint at least 75 cm (29.5 in) long — for this species, swimming length matters as much as raw volume.

What water parameters does a Diamond Tetra need?

Diamond Tetra does best at 24–28 °C (75.2–82.4 °F), pH 5.5–7 and a general hardness of 5–12 °dGH.

What group size does a Diamond Tetra need?

Diamond Tetra is a social species — keep a group of at least 6 so natural behaviour emerges and stress stays low.

Is the Diamond Tetra suitable for beginners?

Yes — Diamond 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

Diamond Tetra

Moenkhausia pittieri

Characidae

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

📷 Dnoerholm · CC BY-SA 4.0 · resized · Wikimedia Commons

Diamond Tetra — Moenkhausia pittieri — 📷 Dnoerholm · CC BY-SA 4.0 · resized · Wikimedia Commons

About

The diamond tetra is a peaceful, deep-bodied characin endemic to the Lake Valencia basin in northern Venezuela. Drab and silvery as a juvenile, it matures into a spectacular fish whose scales scatter light in sparkling green, gold and violet, while males extend long, flowing dorsal and anal fins. Kept as a proper shoal in soft, gently flowing, planted water, it is a hardy, elegant and undemanding community fish that rewards patience as its full colour develops with age. Note that in small numbers it can turn into an occasional fin nipper, so keeping a good-sized group is important.

Care

Keep in a shoal of at least 6 (more is better) in a planted tank of 75 L or larger with soft, slightly acidic water and gentle flow. Keeping a proper group curbs its tendency to nip fins. Its best iridescence develops slowly with maturity, a varied diet and subdued lighting over a darker substrate.

Diet

Opportunistic omnivore that grazes small invertebrates and organic matter in the wild; feed quality dry foods alongside frequent frozen or live daphnia, bloodworm and brine shrimp for colour and condition.

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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Frequently asked questions

What tank size does a Diamond Tetra need?: A Diamond Tetra needs an aquarium of at least 75 litres (19.8 US gallons) with a footprint at least 75 cm (29.5 in) long — for this species, swimming length matters as much as raw volume.
What water parameters does a Diamond Tetra need?: Diamond Tetra does best at 24–28 °C (75.2–82.4 °F), pH 5.5–7 and a general hardness of 5–12 °dGH.
What group size does a Diamond Tetra need?: Diamond Tetra is a social species — keep a group of at least 6 so natural behaviour emerges and stress stays low.
Is the Diamond Tetra suitable for beginners?: Yes — Diamond 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

Temperature24–28°C

Optimal temp.24–27°C

pH5.5–7

Hardness (GH)5–12°d

Carbonate (KH)1–10°d

Adult size6 cm

Min. volume≥ 75 L

Min. tank length≥ 75 cm

Group size≥ 6

Swimming zoneMid

TemperamentPeaceful

Water typeFreshwater

FlowLow

Lifespan~5 yrs

Try in the calculator