What tank size does a Pygmy Corydoras need?

A Pygmy Corydoras needs an aquarium of at least 40 litres (10.6 US gallons) with a footprint at least 45 cm (17.7 in) long — for this species, swimming length matters as much as raw volume.

What water parameters does a Pygmy Corydoras need?

Pygmy Corydoras does best at 22–26 °C (71.6–78.8 °F), pH 6–7.5 and a general hardness of 2–12 °dGH.

What group size does a Pygmy Corydoras need?

Pygmy Corydoras is a social species — keep a group of at least 8 so natural behaviour emerges and stress stays low.

Is the Pygmy Corydoras suitable for beginners?

Yes — Pygmy Corydoras 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

Pygmy Corydoras

Corydoras pygmaeus

Callichthyidae

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

📷 Birger A · CC BY-SA 3.0 · resized · Wikimedia Commons

Pygmy Corydoras — Corydoras pygmaeus — 📷 Birger A · CC BY-SA 3.0 · resized · Wikimedia Commons

About

The pygmy corydoras is one of the smallest catfish in the hobby, a silvery nano fish with a bold black lateral stripe. Unusually for a cory, it spends much of its time hovering and swimming in mid-water as a coordinated shoal rather than only patrolling the bottom. Best kept in large groups in a peaceful nano aquarium, where its schooling behaviour is a constant delight and it feels secure.

Care

Keep 8+ (ideally 10+) in a calm, well-planted nano tank with soft sand and gentle flow. Only house with tiny, peaceful tankmates as it is easily eaten or outcompeted.

Diet

Omnivore with a very small gape; offer micro-foods such as baby brine shrimp, crushed flakes and frozen cyclops. Target-feed to ensure it eats.

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.

Width from aboveStrong · from about 8 months, once they are adult-sized
Corydoras are sexed from directly above, never from the side. Look down at the group while they rest on the sand.
Bristles and cheek spinesA hint only · from about a year
Male plecos grow odontodes — spiny growths on the cheeks and along the leading pectoral rays. Bristlenose males additionally grow branching tentacles across the snout and over the top of the head.

All the methods, with diagrams

Also in these lists

Nano fish Fish for a 54 litre tank Shrimp-safe fish Fish for a first aquarium

Frequently asked questions

What tank size does a Pygmy Corydoras need?: A Pygmy Corydoras needs an aquarium of at least 40 litres (10.6 US gallons) with a footprint at least 45 cm (17.7 in) long — for this species, swimming length matters as much as raw volume.
What water parameters does a Pygmy Corydoras need?: Pygmy Corydoras does best at 22–26 °C (71.6–78.8 °F), pH 6–7.5 and a general hardness of 2–12 °dGH.
What group size does a Pygmy Corydoras need?: Pygmy Corydoras is a social species — keep a group of at least 8 so natural behaviour emerges and stress stays low.
Is the Pygmy Corydoras suitable for beginners?: Yes — Pygmy Corydoras 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

Temperature22–26°C

Optimal temp.23–25°C

pH6–7.5

Hardness (GH)2–12°d

Carbonate (KH)1–8°d

Adult size3 cm

Min. volume≥ 40 L

Min. tank length≥ 45 cm

Group size≥ 8

Swimming zoneAll levels

TemperamentPeaceful

Water typeFreshwater

FlowLow

Lifespan~3 yrs

Try in the calculator