About Corydoras catfish:
Corydoras catfish (Corydoras species, also known as cories) are small, peaceful, schooling catfish. Over 200 species of Corydoras species have been described, and over 50 species are available, although most remain poorly known. Many of the species are very similar in appearance, with only slight variations in color or morphology making them possible to tell apart, although these similar species often come originally from different localities.
In the wild Corydoras often form large mixed schools. They are peaceful fish that need company, of either their own or similar Corydoras species. They should not be mixed with fish that are too nippy or aggressive, although, they can be mixed with some predatory species as their bony armour and spiny fins discourage predation.
These fish should be kept in a tank with fine or rounded gravel to protect their barbels. They appreciate having some hideaways among plants, rocks or ornaments, but will also spend time swimming in the open. Plants are not harmed. High nitrate levels can damage their barbels, so, although they are not overly demanding of water quality, regular partial water changes should not be neglected. The most commonly available species (bronze and albino catfish C. aeneus & peppered catfish C. paleatus) can tolerate quite cool water and can be kept in unheated indoor aquaria. Other species of Corydoras are best kept in heated tanks, although they are less sensitive to temperature fluctuations than tropical fish.
Although there are a number of Corydoras species, most are very similar in terms of their requirements, behaviour, and biology:
around 5 cm for most species, some reach 7 to 8 cm, a few grow larger (eg C. barbatus can reach 12 cm). Dwarf species (C. habrosus, C. hastatus & C. pygmaeus) to 3 cm. More detail in the group descriptions.
Peaceful schooling fish
nearly all community tanks, particularly with small to medium community fish
pH around neutral, soft to quite hard water, low nitrate
22 to 26°C for most species
A good quality tropical granule or small sinking pellet, supplemented with frozen shrimp and worm foods, daphnia, beefheart.
There is little or no difference in most species, although females may be plumper when ready to spawn and males may have more intense coloration. In a very few species (eg C. paleatus), males have a taller dorsal fin.
- Bronze, albino & peppered catfish (Corydoras aeneus & paleatus)
- Masked corydoras & similar species (Corydoras atropersonatus, leucomelas, melanistus & others)
- Leopard corydoras & similar species (Corydoras julii, trilineatus, leopardus & others)
- Panda & arcuatus catfish & similar species (Corydoras panda, arcuatus, metae & others)
- Other species (including Corydoras adolfoi, sterbae, undulatus & others)