A fishpond is an enclosed body of water used to raise fish. It can be made of concrete or earth and it has both an inlet and an outlet to allow water to flow through. Here are some things to consider when you select a site for a fishpond.
Water supply is the most important factor when choosing your site. Fish live, breathe, feed, grow and spawn their young in the pond. So your site must have a good water supply all year round. This water can come from rainfall, run off, dams, springs, wells, streams, lakes or bore holes.
Soil type is also important. The best soil for a pond contains plenty of clay because clay holds water well. Choose soil that can hold enough water in both dry and rainy seasons, and has a minimum of 20% clay and a maximum of 60% clay.
To test your soil for clay content take a handful of wet top soil and mould it into a ball between your palms. Throw the ball into the air and allow it to fall to the ground. If the ball does not break, the soil has enough clay in it to hold water. You can also test soil by collecting wet top soil and rolling it into a continuous thread about 15 centimetres long on your palm. Use the thread to form a ring. If the thread forms a ring without breaking, it means the soil contains enough clay.
Another way to test soil for clay is to dig a hole 60 centimetres in diameter and one meter deep (approximately waist deep). Fill the hole with water and allow it to stand for half a day if it is the dry season. If it is the rainy season, wait about four hours. Some of the water will drain into the soil. Now the soil is ready for your test. Fill the hole with water once more. Using a stick or ruler, measure the depth of the water and allow it to stand for 24 hours. After 24 hours, measure the water again with the same stick or ruler. If the remaining water measures up to half or more than half of the original level, then the soil will hold water for a fishpond.
The third thing to look for when selecting a site for a fishpond is the shape of the land, that is whether the land is flat, hilly, upland or lowland. It is cheaper and easier to construct a fishpond on land that has a gentle slope rather than on flat ground so choose gently sloped landif you can. Also, choose land that has low lying vegetation. Avoid forested areas.
Remember, it is important to consider the safety of your fish when you select your site. If possible, build the pond near your house so it will be easy to watch.
This script was written by Peter Afekoro, Subject Matter Specialist, Ministry of Agriculture and Natural Resources, Nigeria.