Corydoras or Cory fish are small armored catfish native to South America living mostly in freshwater environment.
Taxonomic position of ornamental corydoras catfish
Genus Corydoras is one of the eight genera under the family Callichthyidae (armored catfish) coming under the order Siluriformes (catfishes). More than 170 species have been identified and given an appropriate scientific name.
There are many more ornamental cory catfish species being kept by aquarists which are yet to be classified. These are given C numbers and are under the process of classification.
Armored Corydoras show great diversity in body shape and colors. They are usually small and range from 1-4.5 inches in length.
Salient features of ornamental cory catfish
- These armored catfish have two rows of bony dermal plates for protection, which run along the length of their body: the bony plates overlap.
- The swim bladder is contained in a bony case.
- Mouth of these ornamental cory catfish is usually small and ventral in position.
- These armored cory catfish perform air breathing (rather air swallowing) and expel the air by the anal opening.
- More than breathing, the swallowed air functions as ballast for their buoyancy.
- Strong spine present in the dorsal and pectoral fins.
- One to two pairs of barbels are present; barbels are well developed.
- Adipose fin is present and has a spine at its anterior margin.
- The sensory canal present in the lateral line organ is limited to 1-6 dermal plates.
Distribution of ornamental corydoras catfish
Ornamental Corydoras catfish are endemic to South America. They are distributed east of Andes mountains up to Atlantic ocean. They are mostly present in plains. A few armored cory species are present in higher altitudes.
Corydoras are present in slow flowing streams, rivers, marshes and ponds, usually foraging the shallow bottom. Though they are generally tropical and subtropical some species thrive well in temperate zones. Corydoras are usually found in shoals of a few hundreds to thousands.
Ornamental Corydoras in aquarium
These armored cory catfish are docile and peaceful and can be kept in groups of three and above depending upon the size of the tank. They can be kept in community tanks along with other ornamental fishes.
These ornamental corydoras prefer neutral to slightly acidic waters. However they can be adapted to higher pH. They are sensitive to high nitrate levels in the tank.
Fine sand is recommended as the bottom substrate; hard objects in the bottom may injure the barbels of armored corydoras. Regular exchange of water is necessary to keep the environment of the armored catfish healthy.
Many cory catfish live up to 5 years and life span of even 20 years is not unusual.
Feeding ornamental armored corydoras in aquariums
These ornamental armored fish are bottom dwellers feeding on the detritus and bottom invertebrates. Ornamental cory easily accept pellet and flake feed. It will be ideal if the pellet feed sinks to the bottom as they are shy of remaining at the surface of water.
If ornamental armored cory are kept in community tank, care must be taken to see that some feed reaches the bottom. Ornamental cory can also be fed with live food like mosquito larvae, blood worms, brine shrimp larvae etc.
Breeding ornamental armored corydoras
With good diet and water quality armored cory catfish breed in the tanks and usually release the eggs on the substratum. The eggs of armored cory catfish must be collected and hatched separately in a container. The young cory fry must be fed with micro worms or small bottom settling live feed.
Ornamental armored corydoras have peculiar breeding method in which the female cory drinks the sperms of the male and releases them along with her eggs through the anal opening, fertilizing them.