Taking proper care of fish, managing fish farms and preventing disease is a task that requires effort and attention to detail, right from the point of choosing a site for the fish pond. In Ghana for example, the Ghana Fisheries Commission is mapping out areas that are prime for aquaculture.
- Putting up the Fish Pond
Select the right place for construction of fish ponds. It has to be near a reliable water source, on a gentle slope, and well built. Manage the quality of water – it has to be pure water that is free of pollution, avoid chlorinated water at all costs. A rectangular pond is better for aquaculture because it is easier to stock, feed fish and also harvest. The soil also has to be impervious. Let the fish farm be near a good road so that the fish farmer can access market. Construct dykes around the pond. These dykes have to be at least one meter wide at the top.
- Controlling Weeds
Weeds can either be embedded at the bottom of a pond or they can be floating plants like duckweed. Serious fish farming demands use of an approved aquatic herbicide or use some means of biological control to get rid of them. This has to take place before fertilizing the pond.
- Liming
Adding some lime at the bottom of the pond makes sure that the mud at the bottom has a high pH, making it easier for the phosphorus in the fertilizer to be absorbed. Liming also increases the rate of photosynthesis in the phytoplankton by making carbon dioxide more available. Liming protects the water from extreme changes in the acidity level of the water by creating a buffer zone.
- Laying the Foundations
Fish management for a farmer has to begin with managing the phytoplankton which are food for fingerlings. Phytoplanktons are responsible for the green color of most many ponds. The greater the presence of plankton, the greater the volume of fish produced. Plankton are eaten by water insects and other small organisms which are in turn eaten by fry, fingerlings and mature fish. To keep this system in place, fish care demands that ponds are fertilized using manure or chemical fertilizers. Avoid using too much fertilizer because it can encourage weeds to grow.
Water ought to be retained in the pond for at least three weeks to make sure that the fertilizer is not washed away before it has had any effect. Ensure that the phytoplankton has bloomed before stocking.
- Stocking
Always get stock from reliable, sources. The stock has to be of good quality. Introduce the fingerlings into the pond slowly and gently. Carry them in a bucket and gently tip the bucket slowly into the pond water. An abrupt introduction will result in shock for the fingerlings which may die.
- Feeding Fish
After stocking, allow fish to feed on plankton for about a month before beginning to feed them. After that, you may feed them with fish feeds purchased from reliable manufacturers or mixed on your fish farm. Take care to ensure that feeds meet all nutritional requirements and that fish are not overfed or underfed. Feeding should take place twice a day and care should be taken to be sure that fish have a healthy appetite and are gaining weight. If the fish show a low enthusiasm for feeding, it is possible that they are unhealthy. Weigh the fish every two weeks or at least every month to check that they are gaining weight as part of fish care.
- Disease Prevention
Disease prevention has to begin from the beginning. Only buy healthy stock from a reputable supplier. Use spring or borehole water because it does not contain pathogens. If any fish are found dead, they should be removed immediately and cause of death established. Always avoid overstocking. Keep equipment clean and limit access to the farm to staff and people who are wearing protective clothing.
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