HISTORICAL FACTS

Many of the popular tropical aquarium cat fishes originate from South and Central America, Africa and Asia. Most are rather drably colored, mainly because they need good camouflage to avoid predation. As they usually frequent the bottom, the ideal colors are brown and black. Many have poor sight, as they are often nocturnal or live in silt-laden waters. To compensate for this, catfishes have developed barbells, which recovered in taste receptors. Barbells may be long and used for hunting, basin the pummeled or, as in the Cordovans catfishes, short and used to burrow and tease their way into the gravel to detect food or insects. Some catfishes scavenge at the bottom for tasty morsels, others amendatory swimmers that feed mainly on insect larvae. Large predatory species hunt for small live fish, a few feed on fruit and seeds and some of the most bizarre species are parasitic - even to the extent of feeding on other catfishes.
Some of these 'cats' have developed large, rubbery, sucker-type mouths with which they remove the algae and any other protein-rich coatings that cover plants, rocks or gravel. Some catfish species cover great distances, both in daylight and during the hours of darkness. They may be specialist feeders, whereas the catfishes that remain hidden in a cave for most of the time will tend to feed on virtually anything, because they have to take what they can, rather than hunt for particular food.
Many cat fish species are quite capable of eating very large fish or other large aquatic creatures. All in all, they represent a very mixed and fascinating group. It is a good idea to have at least one cat fish in every aquarium, as they tend to clear up and eat any waste or leftovers that other fish ignore. Do not look on them just as scavengers, however; they are interesting fish in their own right and appreciate proper feeding, rather than living off the scraps left by other fishes in the community aquarium.
You will get a huge variety in South American cat fishes, some of them are very small in size and some species are very large. African species comprises Electrical fish and Nile fish, their belly is dark but have a white back. In the Pacific Ocean there is no cat fish except white fish. The color of the white fish from sides is blue gray to blue black and it can be spotted. You will get one more species of cat fish in Singapore that is yellow cat fish. They are foreign species from Singapore, China there is nothing Indians in this cat fish species.

Classification of Cat Fish

Phylum Chordata
Subphylum Vertebrata
Class Osteichthyes
Order Cypriniformes
Suborder Nematognathi

Phylum Chordata includes those animals which reside in the top of the food chain. A primary common feature of the phylum chordate is notochord it is a rod like structure which extends to the length of the organism. Notochord is necessary and must be present when there is development in the body parts of this cat fish. Subphylum Vertebrata has chordates with backbone