Fish Maintenance work

 

Maintenance work

. Clean up outlet canals

• Upgrade water inlet canals

• Erosion control works near the ponds

• Dry out the pond for a period of 15days at least according to weather conditions (February, August)

Fertilizing the Ponds

• Lime will have to be used to correct the acidity of peat soils and of the water in areas where they occur'
• To obtain high yields with T. nilotica, T. macrochir and common carp (C. carpio), fertilization of the ponds has to be carried out regularly. Either organic or inorganic fertilizers may be used, but recent increases in the price of chemical fertilizers may greatly limit their use in Rwanda, taking also into account local transport problems, especially in remote areas. Inorganic fertilizers include superphosphates, ammonium compounds and urea. Organic fertilizers might include animal manures, vegetable compost and artificial manure; the last named is made by composting vegetable matter and adding urea or some other source of nitrogen.

Fish farming associated with livestock

There is a technique that consists of associating fish farming with swine rearing, chickens, rabbits or ducks above or nearby fish ponds. This technique allows to double the productivity of a pond through fertilization and to obtain additional output due to this breeding on the same unit of area.