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Angling for profit

Angling for profit "IF you give a person a fish, he will have food for one day. But if you teach him to fish, he will have food for the rest of his life." This ancient Chinese proverb serves as the motto for a group called Tear Fund - a UK-based NGO. The latest issue of their journal Footsteps, offers innovative' ways of fish farming.

Like crop farming, fish farming. requires land in the form of a pond and seeds in the form of fingerlings or finger-sized baby fish. Fish food serves as the fertiliser and growing fish requires as much care as any crop.

Ponds can, be of two types - contour ponds built in naturally sloping land and dug out ponds built on flat land. The ideal site for a pond would be one with a reliable water source, but soil with water retention capacity will also do. For family purpose, several small-sized ponds of about 150 sq m are recommended. A sloping bottom surface would ensure drainage of the entire water at the time of harvesting, which can be difficult in larger ponds.

The height of the pond above the water surface should be about 30 cm with gently sloping and compacted sides. The shallow side is reserved for the inlet pipe which has a screen on one end to prevent the fish from escaping. The overflow pipe, also screened, is laid out in the bank wall on the deep side. To protect the pond walls from eroding and adding mud into the pond, grass is grown on the banks.

Small rocks should cover the pond bottom, where the inlet pipe pours water, to prevent it from sinking in. The pond is filled with water two weeks before the stocking of fish. In case the pond bottom is not watertight, it can be sealed with the help of artificial linings of polyethylene, rubber or cement. As these linings are expensive, gleying and clay lining offer a cheaper alternative.

For gleying, the pond is first dug and cleared of rocks and stones and the surface compacted. Then a layer of manure, preferably pig manure, is laid out. ' This two to three cm thick layer of manure is covered with another layer of fresh grass cuttings or finely chopped banana leaves. This is topped with a layer of soil and stamped down into place by feet. The soil layer allows air exchange to take place, which assists in the biological process of gleying occurring below.

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