Fish
Pygmy Cory
Corydoras pygmaeus
Origin: The pygmy cory comes from the Madeira River basin in Brazil and neighbouring parts of the upper Amazon. It inhabits small tributaries and streams with soft, slightly acidic water, sandy beds, and plant thickets.
Also known as: Pygmy corydoras, Corydoras pygmaeus
Fact sheet
- Size
- 3 cm
- Lifespan
- 3 years
- Minimum tank size
- 40 L
- Temperature
- 22–26 °C
- pH
- 6–7.5
- Hardness GH
- 2–15 °dH
- Temperament
- Peaceful
- Social behavior
- Schooling
- Group size
- 10+ individuals
- Swimming zone
- Middle, Bottom
- Diet
- Omnivore
- Jumps out
- No
- Eats plants
- No
Overview
The pygmy cory is one of the smallest corydoras, reaching only about 3 cm. Unlike most of its relatives, it spends much of its time not on the bottom but in midwater, moving in a tight shoal. This makes it an ideal choice for nano aquariums. Keep it in a large group of at least 10 — only in a big shoal do pygmies behave naturally and stop hiding.
Appearance
The body is tiny and slender for a cory, up to 2.5–3 cm long. Colour is silvery-grey with a clear horizontal black stripe from head to tail and a dark spot at its base. Females are slightly larger and fuller than males. Its small size makes the pattern look especially sharp.
Care
A tank of at least 40 L with soft sandy substrate, live plants, and calm flow. Temperature 22–26 °C, pH 6.0–7.5, hardness GH 2–15. Clean water, gentle filtration without strong current, and regular water changes are needed. The small fish is sensitive to water quality.
Feeding
An omnivorous micro-predator with a tiny mouth. Food must be small: micro-pellets, crushed tablets, and small live or frozen fare — brine shrimp nauplii, cyclops, and micro-worm. It catches food both in midwater and on the bottom. Feed once or twice daily in small portions.
Compatibility
A very peaceful schooling fish for a nano tank. Ideal with small rasboras, microrasboras, dwarf tetras, and shrimp. Any large fish may mistake the pygmy for food. Keep in groups of at least 10.
Breeding
Breeding is possible in soft water. Trigger spawning with a cool water change. The female sticks single eggs to plants and glass. Remove the adults; the tiny fry need infusoria and 'green water' — the hardest stage.
Fun facts
The pygmy is one of the few corydoras that swims in a shoal in midwater rather than only rooting on the bottom. Its small size lets it be kept even in nano tanks. In a tight shoal the fish freeze in unison and then move off again.