Corydoras pygmaeus: A Comprehensive Guide

Corydoras pygmaeus, also known as the Pygmy Cory, is a popular choice among aquarists due to its small size and peaceful nature. This guide covers everything you need to know about Corydoras pygmaeus, from their natural distribution and habitat to their dietary needs and spawning and best practices.

Distribution and Habitat

Corydoras pygmaeus are native to the freshwater rivers and tributaries of Brazil. They are primarily found in the Madeira River basin, where they inhabit slow-moving waters with sandy or muddy substrates, often accompanied by leaf litter and aquatic vegetation.

Size and Appearance

Corydoras pygmaeus are among the smallest species of Corydoras, growing to a maximum size of about 1 inch (2.5 cm). They have a sleek, silver body with a distinctive black horizontal stripe running along their side, from the snout to the tail.

Water Parameters

Maintaining optimal water conditions is essential for the health of Corydoras pygmaeus:

  • Temperature: 72-79°F (22-26°C)
  • pH: 6.4-7.4
  • Hardness: 2-15 dGH

These fish thrive in well-oxygenated water with a gentle flow, replicating their natural habitat.

Tank Mates

Corydoras pygmaeus are peaceful and social fish, making them ideal for community tanks with other small, non-aggressive species. Suitable tank mates include:

  • Small tetras
  • Rasboras
  • Pseudomugils
  • Dwarf shrimp
  • Snails

Avoid housing them with larger or more aggressive fish that might intimidate or harm them.


In the wild, Corydoras pygmaeus are omnivores, feeding on small invertebrates, plant matter, and detritus. In captivity, they thrive on a varied diet:

  • High-quality sinking micro-pellets or wafers
  • Live or frozen foods such as bloodworms, daphnia, and baby brine shrimp
  • Blanched vegetables like peas and zucchini

A varied diet ensures their vibrant coloration and overall health.


Corydoras pygmaeus are active and social, typically found in groups. Unlike many other Corydoras species, Pygmy Corys often swim in the middle of the water column rather than sticking solely to the bottom. They are best kept in groups of at least six to promote natural behaviors and reduce stress.


Breeding Corydoras pygmaeus in captivity is relatively straightforward, making them a favorite among aquarists. Key points include:

  1. Conditioning: Feed the breeding group a high-protein diet, including live and frozen foods, for several weeks.
  2. Breeding Tank: Set up a separate breeding tank with soft, slightly acidic water and a temperature around 75°F (24°C). Provide plenty of hiding spots and smooth surfaces for egg-laying.
  3. Spawning Process: Males will chase females, who lay adhesive eggs on surfaces such as plant leaves or aquarium glass. Remove the adults after spawning to prevent egg predation.
  4. Hatching: Eggs typically hatch within 3-4 days. Feed the fry infusoria or liquid fry food until they are large enough to consume baby brine shrimp.

Fun Facts

  • Corydoras pygmaeus are one of the few Corydoras species that frequently swim in the midwater region, adding dynamic movement to the aquarium.
  • They are peaceful and excellent for community tanks, contributing to a balanced aquarium ecosystem by cleaning up leftover food from the substrate.
  • Pygmy Corys are known for their playful and active nature, often seen darting around the tank in groups.


Corydoras pygmaeus, with their small size and peaceful demeanor, make a delightful addition to any freshwater aquarium. By understanding their natural habitat, dietary needs, and care requirements, aquarists can ensure these charming fish thrive in captivity. Whether you're a novice or an experienced fish keeper, Corydoras pygmaeus offers a glimpse into the world of dynamic and interactive nano fish.

Looking to add Corydoras pygmaeus to your aquarium? We recommend purchasing from trusted suppliers like The Wet Spot Tropical Fish and Dan's Fish for high-quality, healthy fish. These reputable retailers offer a great selection and expert advice to ensure you find the perfect fish for your tank.