|Better Farming Series 35 - Better Freshwater Fish Farming: Further Improvement (FAO, 1986, 61 p.)|
6. The easiest way to make an even bigger pond is to add a new part to one of your old ponds.
7. You can add a new part to your old pond of 15 x 15 metres. You can make it twice as big. You can make it 15 x 30 metres and still build the banks in the same way that you built them for the old part of the pond.
New outlet and overflow
8. Booklet No. 29, Items 42 to 48, tells you how to make a smaller pond bigger.
9. If you do not want to make your old pond bigger, you can build one or more new ponds of 15 x 15 metres next to your old pond ...
or in another place.
10. You can also build a pond of 20 x 20 metres and still dig the bottom and build the banks in the same way as you did for your old ponds.
11. The top of the banks of a 20 x 20 metre pond should still be 1.50 metres wide as they were with your 15 x 15 metre ponds.
The banks of pond
12. The water should be at least 0.60 metre deep in the shallow part and at least 0.90 metre deep in the deepest part.
Keep the water deep
13. If you want a still bigger pond, you can build one of 20 x 30 metres, 20 x 50 metres or even 30 x 50 metres. The top of the banks of ponds this size should also be 1.50 metres wide but, because these ponds are bigger and deeper and hold much more water, the bottom part of the banks should be stronger than the banks you built for your smaller ponds.
14. Since you will be digging bigger and deeper ponds, you will take out more soil. Put all the soil you dig out on the lower part of the banks. This will make them thicker and stronger.
15. The drawing below will show you what the banks should look like when you are finished.
The banks of a pond
16. However, if you build ponds of this size, you should build them a little deeper. They should be at least 0.75 metre deep in the shallow end and at least 1.00- 1.20 metres deep in the deepest part.
Keep the water deep
17. If you live in a place where the temperature falls below 20°C, make your ponds 1.50- 1.80 metres deep. The water will be warmer in the deepest part and your fish can go there during the colder part of each day.
Remember when ponds are side by side, you will need only one bank between two ponds (see Item 45, Booklet No. 27). If you are building two ponds side by side at the same time, you can make the top of the bank between them 1.00 metre wide instead of 1.50 metres.
One bank between two ponds