|Better Farming Series 30 - Better Freshwater Fish Farming: the Fish (FAO, 1981, 48 p.)|
47. A new nursery pond of about 7 by 7 metres, or about 50 square metres, will be large enough to grow the baby fish you will need.
New nursery pond
48. A nursery pond can be built just like a big pond but since the nursery pond is smaller the banks need not be as high or as wide.
49. You can build your nursery pond with an inlet, outlet and
overflow like these you used in your big pond.
50. You can also use a shallow trench to let water into your nursery pond (see Booklet No. 29, Items 84 and 85), and use a siphon to drain the water out (see Booklet No. 29, Items 114 to 123), but you will still need an overflow to control the water level in the nursery pond.
51. You will also need a crib to held the fertilizer in your new nursery pond.
52. If you build your new nursery pond next to your big pond so that they share a bank, you will only need to build three new banks for it.
53. If you grow baby fish near your pond, you will not have to carry them far and they will not be hurt when you are carrying them.
Grow baby fish near the pond
54. Fill your nursery pond with water and fertilize it with compost, animal manure or plant material as you did with your big pond. Wait for the water to turn green.
55. Now you are ready to put fully grown male and female fish into your nursery pond. A fully grown Tilapia nilotica is about 20 centimetres long.
56. Be careful to put the right number of male fish and female fish into your nursery pond. The drawing shows you how to see the difference between male fish and female fish.
Difference between male and female fish
57. If you are using your old smaller pond of 10 by 10 metres as a nursery pond and you are using Tilapia nilotica, you will need to put 20 fully grown male fish and 80 fully grown female fish into the pond.
Use Tilapia nilotica in the old smaller pond
58. If you have built a new nursery pond of 7 by 7 metres and you are using Tilapia nilotica, you will need to put 10 fully grown male fish and 40 fully grown female fish into the pond.
Use Tilapia nilotica in a new nursery pond