Mini Cory – Gastrodermus nanus

Mini Cory (Gastrodermus nanus)

The Mini Cory, Gastrodermus nanus, is a small and peaceful cory-type catfish with a slender body, delicate dark striping and lively shoaling behaviour. Still widely known in the trade as Corydoras nanus or the Little Corydoras, this attractive South American bottom-dweller is best kept in a mature community aquarium with soft sand, clean water and a proper group of its own kind. Although smaller than many common Corydoras-type catfish, it is active, sociable and very rewarding when kept with calm tank mates.

Common Name:
Mini Cory, Little Corydoras, Nanus Cory, Dwarf Cory, Corydoras nanus.

Scientific Name (Latin):
Gastrodermus nanus
Formerly and still widely traded as Corydoras nanus.

Maximum Size:
Up to around 4.5 cm standard length, with many aquarium specimens remaining around 4–5 cm.

Water Type:
Freshwater

Origin / Natural Habitat:
Native to northern South America, including the Suriname and Maroni River basins in Suriname and the Iracoubo River basin in French Guiana. FishBase notes that only a small number of wild specimens have been collected, including fish from a shallow creek with moderate current, sandy to sandy-muddy bottom and subdued light.

Water Parameters:
Temperature: 22–26°C
pH Range: 6.0–7.5
Hardness or Salinity: Soft to moderately hard freshwater; clean, stable water with good oxygenation is important.

Temperament:
Peaceful and sociable. Mini Corys are gentle community fish and should not be kept alone. They do best with calm, small to medium-sized tank mates and can be stressed or outcompeted by large, aggressive or very boisterous fish.

Diet:
Omnivorous bottom-feeder. Offer fine sinking catfish pellets, micro granules, small wafers, frozen daphnia, cyclops, brineshrimp, small bloodworm and other suitably sized foods. They will forage across the substrate, but should not be expected to live only on leftovers from fish feeding higher in the aquarium.

Minimum Tank Size:
A minimum of 60 litres is recommended for a group, with larger aquariums preferred for mixed community setups. A longer aquarium footprint is more useful than extra height because this species spends much of its time on or near the bottom.

Behaviour & Activity:
An active, small cory-type catfish that spends much of the day sifting sand, exploring open patches and resting in loose groups. Keep at least 6 individuals, with 8 or more preferred for confidence and natural behaviour. Like other Corydoradinae catfish, it may occasionally dart to the surface to gulp air, so always leave clear access to the water surface.

Aquarium Category:
Community Fish
Suitable with peaceful small tetras, rasboras, pencilfish, dwarf cichlids with care, small livebearers, gouramis, Otocinclus and other calm community fish. Avoid large predatory fish, aggressive cichlids, rough bottom-dwellers, fin-nippers and any fish large enough to swallow or intimidate them.

Special Requirements or Care Notes:
Soft sand is strongly recommended to protect the barbels and underside while foraging. Provide plants, driftwood, leaf litter, caves, shaded areas and open sand patches. Keep the substrate clean with regular maintenance, as small cory-type catfish are sensitive to poor bottom hygiene and unstable water quality. This species is less commonly available than many standard corys, so careful acclimation and a mature aquarium are recommended.

Suitable for:
Beginner to intermediate fishkeepers

Availability:
Occasional in trade / Specialist import or captive-bred where relevant

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Please note that Mother Nature is a wonderful thing, and variation in patterns and colours will occur — that is part of the unique beauty of these animals.