Pygmy corydoras (Gastrodermus Pygmaeus)

*Note: Images are used as an example only. Due to the nature of live animals, colouration, size and patterns may vary.*

Pygmy Corydoras
Scientific Name: Gastrodermus pygmaeus
(Also known as the Pygmy Cory or Pygmy Catfish.)

Overview
The Pygmy Corydoras is a tiny, peaceful bottom-dwelling catfish known for its compact size, silver-grey body, dark horizontal stripe, and playful shoaling behaviour. Unlike many Corydoras species, Pygmy Corydoras frequently spend time swimming in the midwater as well as foraging along the substrate. Their small size and peaceful nature make them an excellent choice for planted nano and community aquariums.

Key Features

• Extremely small Corydoras species ideal for nano aquariums
• Distinct dark horizontal stripe running along the body
• Peaceful and highly social shoaling behaviour
• Frequently swims in the midwater as well as along the bottom
• Excellent choice for planted and peaceful community aquariums

Care Level: Easy
Hardy and adaptable when kept in stable, clean water. Best results are achieved when kept in groups and provided with a mature aquarium and suitable substrate.

Habitat Requirements
Environment Type: Freshwater
Tank Size: Best results in 40+ litres; can be kept in smaller aquariums when appropriately stocked and maintained
Temperature: Ideally 22–26°C; tolerates approximately 20–28°C
Water Parameters: pH 6.0–7.5 preferred; stable conditions are more important than exact values
Water Hardness: Soft to moderately hard water
Water Flow: Gentle to moderate
Aquascape: Fine sand or smooth substrate, plants, driftwood, and sheltered areas provide ideal conditions; leave open areas for swimming and foraging

Diet
Primary Diet: High-quality sinking nano pellets, micro wafers, and appropriately sized catfish foods
Variety: Frozen or live foods such as baby brine shrimp, daphnia, cyclops, and bloodworms provide valuable variety
Flexible Options: Will forage for small foods throughout the aquarium, particularly in mature planted setups
Feeding Frequency: Small meals once or twice per day, ensuring food reaches the bottom and is available to the entire group

Compatibility
Tank Mates: Peaceful nano fish such as small rasboras, tetras, Pseudomugil species, and other peaceful Corydoras, as well as suitable freshwater shrimp
Avoid: Large, aggressive, or highly predatory species that may eat or intimidate them
Temperament: Very peaceful and social; best kept as a group

Size and Lifespan
Adult Size: Approximately 2.5–3 cm
Typical Lifespan: 3–5 years with consistent care

Behaviour and Activity
Pygmy Corydoras are active, social fish that display fascinating shoaling behaviour. They regularly move together around the aquarium and may spend considerable time swimming through the midwater rather than remaining exclusively on the substrate. They also enjoy resting on leaves, hardscape, and the substrate before suddenly becoming active again as a group.

Special Requirements or Considerations
Keeping Pygmy Corydoras in a group is essential for their confidence and natural behaviour. A group of at least six is recommended, with larger groups often displaying more natural and interesting shoaling behaviour. Fine sand or smooth substrate is preferred to help protect their sensitive barbels. Because of their small size, ensure all tank mates are peaceful and that food is appropriately sized.

Ideal For

• Nano and planted aquariums
• Peaceful community setups
• Aquarists seeking an active, social bottom-dwelling species
• Beginners looking for a hardy and peaceful nano fish
• Aquariums where midwater and bottom activity are both desired

Additional Notes
Pygmy Corydoras are one of the smallest and most versatile Corydoras available. Their combination of tiny size, peaceful temperament, and unusual midwater shoaling behaviour makes them particularly appealing for planted community aquariums. Keeping them in a suitably sized group, providing a soft or smooth substrate, and offering a varied diet will encourage natural behaviour and help maintain excellent health.