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Introduction to Catfish (Ikan Keli)

Catfish (order Siluriformes) are a very diverse group of bony fish. Named for their prominent barbells, which resemble a cat's whiskers (though not prominent in all members of this order), catfish range in size and behavior from the heaviest, the Mekong giant catfish from Southeast Asia and the longest, the wels catfish of Eurasia, to detritivores (species that eat dead material on the bottom), and even to a tiny parasitic species commonly called the candiru, Vandellia cirrhosa. There are armour-plated types and also naked types, neither having scales. Despite their common name, not all catfish have prominent barbels; what defines a fish as being in the order Siluriformes are in fact certain features of the skull and swimbladder. Catfish are of considerable commercial importance; many of the larger species are farmed or fished for food. Many of the smaller species, particularly the genus Corydoras, are important in the aquarium hobby.

A Note to Non-Farmers

A large number of information requests that are received by Extension Offices for fish farming are from non-farming, urban
residents. Most farmers were born and raised on a farm. Very few learned how to farm as an adult. This puts the non-farmer at a considerable disadvantage.

Non-farmers will need to go through a period of on-the-job training. Are you the kind of person who does most of the maintenance and repair work? Can you put up with outdoor work during bad weather and odd hours? If so, great - these are skills and tolerances you will need on a fish farm. If not, you may wish to reconsider before getting into fish farming. In addition, farming today requires much more than just being able to produce a crop. Successful farmers must have a sound understanding of the economics of their operation, keep good records and work to find the best markets for their product.

Systems for Growing Catfish

Three systems for growing channel catfish have proven economical. Levee ponds are constructed by building earthen levees on all four sides of a relatively flat area to hold from 4 to 6 feet of water. Water is usually supplied from a well and the ponds are built to be self-draining. Up to 4,500 fish per surface acre of levee pond can be grown if aeration equipment is used and fish are harvested at the 1 to 2 kg size.

Watershed ponds are constructed on steeper slopes by building a dam across a draw or ravine to catch runoff water. If built with a fairly flat bottom they can be used for commercial catfish farming. To avoid weed problems, water depth should be a minimum of 4 feet. A disadvantage to most watershed ponds is the lack of control over refill. One way around this is to build a series of ponds, one above the other. The lowest pond is harvested first, so as higher ponds are drained they fill the one below.

Deep ponds are likely to experience low oxygen problems in the fall when oxygen poor bottom water mixes with upper water. Because of this problem, ponds with an average depth of more than 6 feet should not be stocked with more than 2000 catfish per surface acre, unless special equipment is used to keep top and bottom waters mixed.

Cages are used to grow catfish in existing ponds and lakes where harvesting loose stocked fish would be difficult or impossible. Catfish can be stocked into cages at eight to ten fish per cubic foot and grown to a size of 1 to 2 kg. Catfish do well in cages provided that they are not disturbed, the cage mesh does not become clogged with algae (“moss”) and no more than 1,000 kgs of fish per surface acre of Farmingpond are grown. The pounds grown per surface acre must be kept low to reduce the chance of low oxygen conditions.

Other systems for growing catfish are being developed. Currently these systems are recommended only for those willing to accept a higher level of risk, or those planning only a small scale operation. Raceways are tanks or channels in which large volumes of flowing water supply oxygen and carry away wastes, allowing fish to be produced very densely. Given ideal water temperatures, they still use about 4 times as much water to raise catfish as ponds. Recirculating systems filter and recycle water allowing fish to be grown year round indoors where growing temperatures can be maintained. Potential for fish kills in these systems is high due to unreliable filtration systems.

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