Pygmy Corydoras

Corydoras pygmaeus

Catfish

One of the smallest Corydoras species, the Pygmy Cory is a true nano fish. Unlike most of their bottom-dwelling cousins, Pygmy Corys are famous for hovering and schooling in the mid-water area. They are extremely peaceful but very shy, requiring a proper school to feel secure. A soft sand substrate is absolutely required to protect their delicate barbels.

At a Glance

Adult Size3 cm
Body ShapeFusiform
Growth RateModerate
TemperamentPeaceful
Water TypeFreshwater Only
Flow PreferenceModerate
Waste OutputLow
StockingSchool of 6+

Tank Requirements

Minimum Volume38 L
Minimum Length45 cm
FlowModerate
Water TypeFreshwater Only
Must-Haves in the Tank
Sand (Sifters)Plants - Densely covered

Water Parameters

Temperature2226°C
pH67.5
Hardness215 dGH

Temperament & Compatibility

Aggression LevelPeaceful
0/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least6 fish
Max per TankNo limit
Can Live Alone?No — needs a group
Behavior Traits
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)Hyperactive / Fast Swimmer

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard

The standard form found in the aquarium trade. Must be kept in a group of at least 6 (though 10+ is highly recommended) to exhibit their natural mid-water hovering behavior and avoid severe stress.

Differs in 1 trait from base species

Also known as: Wild Type

Behavior Traits
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)Hyperactive / Fast Swimmer

Pygmy Corydoras Care Guide Summary

The Pygmy Corydoras, scientifically known as Corydoras pygmaeus, belongs to the Catfish family group. Adults reach a maximum size of approximately 3 cm and have a fusiform body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a low level of biological waste.

To thrive, the Pygmy Corydoras requires a freshwater only aquarium with a minimum volume of 38 litres and a tank length of at least 45 cm. Water temperature should be maintained between 22°C and 26°C, with a pH range of 67.5 and a general hardness of 215 dGH. A moderate water flow is preferred.

The Pygmy Corydoras is a rewarding species to keep, provided its core environmental needs are met. The Pygmy Corydoras is typically available in one standard form.

Pygmy Corydoras Habitat Setup

When setting up an aquarium for the Pygmy Corydoras, a moderate water flow best suits their natural preferences. Because this species occupies the mid-level and bottom zones, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement and sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include a sand substrate to accommodate their sifting behaviour and dense planting to provide cover, break sightlines, and reduce stress.

Pygmy Corydoras Compatibility Notes

Classified as peaceful, the Pygmy Corydoras is a schooling species that feels most secure in a sizeable group, where natural shoaling behaviour reduces stress and brings out their best colours. Selecting tankmates that favour different water layers from the mid-level and bottom zones can help reduce competition and territorial overlap.

Frequently Asked Questions About Pygmy Corydoras

How big does Pygmy Corydoras get?+
Pygmy Corydoras (Corydoras pygmaeus) typically reaches a maximum adult size of approximately 3 cm. They have a fusiform body shape and a moderate growth rate.
What tank size does Pygmy Corydoras need?+
A minimum aquarium volume of 38 litres and a tank length of at least 45 cm are recommended for Pygmy Corydoras. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Pygmy Corydoras need?+
Pygmy Corydoras thrives in freshwater only conditions with a temperature range of 22–26°C, a pH between 6 and 7.5, and a general hardness of 2–15 dGH. A moderate water flow is preferred.
Is Pygmy Corydoras peaceful or aggressive?+
Pygmy Corydoras is classified as peaceful with an aggression score of 0 out of 10. They are generally well-suited to peaceful community tanks.
How many Pygmy Corydoras should be kept together?+
Pygmy Corydoras is a schooling species and should be kept in groups of at least 6. Larger groups help distribute aggression and encourage natural schooling behaviour.
Does Pygmy Corydoras have any special tank requirements?+
Yes. Pygmy Corydoras benefits from sand (sifters) and plants - densely covered in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

Similar Species

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Panda Corydoras

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