Article reprinted from
An Introduction to Corydoras Catfish
Category : Tropical Articles
Published by Fishy-Fishy on 26/03/2006
An introduction to Corydoras Catfish by member Fishy-Fishy.

Why Keep Corydoras?

The corydoras genus comes from the Callichthyidae family and contains over 150 specific species with still more being discovered. All corydoras come from South America. They spread from Columbia in the north to Argentina in the south. They are small, with most species growing between 1 and 3 inches long. They are peaceful fish that live in large groups which tend to frequent the bottom of streams and rivers, although there are a few mid-water swimming exceptions. Their peaceful nature, beautiful markings and hardiness make them perfect additions to community aquaria.

Cory Sterbai
© vchawker/


Physiology of a Cory
Most corydoras have a similar appearance, with the differences being in size, colour and markings. They have four sensitive barbells around their mouths to help them find food hidden in the substrate. They have no scales but have ‘armour’ in the form of bony plates to protect them. These form two rows along the corydoras’ body. Corydoras sometimes swallow air from the surface of the water, which passes into its swimbladder where the oxygen is extracted. This ensures their survival in oxygen-starved water.

Four barbells can be clearly seen around the mouth on this Albino Cory
Photo © Hazzy/


A Short Guide to Keeping Corys
Corydoras are very popular for community aquariums, and with good reason. They are a peaceful and easy to keep fish that give some interest to the lower part of the aquarium.
They should be kept in groups of 6 or more because in a smaller group, they may be shy and inactive and become stressed. They will get on with most tankmates, providing they are of similar size, but do prefer a sand substrate as gravel can damage their barbells. They will take most foods but a sinking pellet specifically designed for catfish is best. Bear in mind that they have very small mouths so smaller pellets are ideal. They are also very partial to bloodworm!
Some corys will breed in a community aquarium, but it is best achieved in a species tank. Females tend to be either larger or more rounded than males; this varies from species to species.

Cory's should be kept in groups
Photo © newbie62/


Popular Corydoras Species

© Erdington Aquatics
Bronze Cory (corydoras aeneus)
Probably the most popular cory, these are available in most aquatic shops. They are fairly easy to breed and are available in albino and longfin varieties.
Temp: 21-26C
pH: 6.5-7.5
Size: 3"

© Erdington Aquatics
Peppered Cory (corydoras paleatus)
Another popular cory, these are slightly smaller and have mottled markings that are good camouflage.
Temp: 18-25C
pH: 6-7.5
Size: Just under 3"

© vchawker/
Panda Cory (corydoras panda)
These fish get their name from the black markings around their eyes which also ensure their continuing popularity with fishkeepers. These are one of the smaller corys.
Temp: 22-25C
pH: 6-7.5
Size: 2"

© Erdington Aquatics
Pygmy Cory (corydoras pygmaeus)
This is one of the smallest cory species and is a mid-water swimmer. They like to rest on large leaved plants instead of on the substrate like most other corys.
Temp: 22-26C
pH: 6.5-7.5
Size: 1"

© Erdington Aquatics
Adolfo’s Cory (corydoras aldofoi)
This colourful cory is another popular addition to the community aquarium but prefers softer water than most corys.
Temp: 20-26C
pH: 5.5-7
Size: 2"

  Seuss’ Cory (corydoras seussi)
This cory has a slightly elongated snout and striped markings on its tail and fins.
Temp: 22-25C
pH: 6-8
Size: Just under 3"
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