Ornamental freshwater aquarium catfish have spread to all the continents except Antarctica with unique characters for respective regions.
Taxonomic position and salient features of the ornamental aquarium catfish
The aquarium catfish come under the order Siluriformes. More than 2000 species have been identified and the list is ever growing. There are many specimens awaiting classification.
The prominent feature of them is the presence of prominent barbels (like cat whiskers). However there are exceptions to this character.
Most of the ornamental aquarium catfish are benthic in nature and are bottom feeders. Because of the presence of heavy bony head and reduced gas bladder they sink to the bottom when not swimming and are negatively buoyant.
Most of these ornamental catfish have wide opening ventral mouth suited to their bottom feeding habit. They feed rather by sucking and gulping than biting and tearing the food.Some ornamental species have suckermouth by which they can attach themselves to a moving object.
They have modified maxilla to support barbels and hence cannot protrude their mouth. These ornamental pets have up to four pairs of barbels.
They have a well developed Weberian apparatus and reduced gas bladder allowing them to hear well and also make sounds.
They have no scales and some families have bony plates covering and protecting their body as in the case of Corydoras. Most of them have naked scaleless slimy body. Some species use the skin for passive cutaneous respiration.
Except electric catfish all the others have spiny ray on their dorsal and pectoral fins, which they use for their defence. Some species have these spines hollow and can deliver poisonous proteins through the spine on to the predators.
Nearly half of the species show sexual dimorphism with anal fin modification into intromittent organ or accessory structures of reproduction.
Distribution of the ornamental aquarium catfish
Except Antarctica, these ornamental species inhabit all the other continents. Of all the known aquarium catfish more than 50% live in North and South Americas. Diverse varieties are found in Americas, Africa and Asia.
They inhabit all the possible freshwater habitats and eight families live underground and three of them also live in caves. There are many catfish which live in saltwater.
Cory catfish or Corydoras are inhabitants of southern North America and South America. Synodontis sp. to which upside down catfish belong inhabit the lakes and rivers of Africa.
Keeping ornamental catfish aquarium
More information on Corydoras is given in the page on Corydoras. Here you find information on other aquarium catfish. Most of these species are hardy, docile and get along well with aquarium mates in a community aquarium.
As they tend to burrow and scoop the bottom, fine sand or gravel may be provided as substrate. Hard objects may injure their barbels. Many of them are shy in nature and hiding places must be provided in the aquarium. Subdued lighting is preferred.
Feeding aquarium catfish
Most of these ornamental pets are omnivores. They also eat on the algal growth. They are benthic feeders feeding on the bottom detritus and bottom invertebrates like worms, insect larvae and shrimp.
Exceptions are the upside down aquarium catfish and aquarium glass catfish. These feed from the water column and the water surface. These ornamental species accept pellet feed and also relish dried worms.
The feed should reach the bottom of the tank for it to be available for them in a community aquarium. In many tanks these ornamental pets are kept as bottom cleaners and glass cleaners.
Breeding aquarium catfish
Some of the ornamental species like corys, pangasius spp. and bristlenose have been bred successfully in captivity. In some ornamental species parental care is seen.