Stocking Density in Stocking Ponds

• The stocking ponds are generally stocked with fingerlings which are about 75-100 mm in size.
• For increasing fish production, the selection of fish with desirable qualities is the most important biological factor. Since fish with the shortest food chain give the highest production, phytophagous, herbivores, omnivores and detritus feeders are preferred for culture in stocking ponds.
• For rearing of fish, either monoculture or polyculture in any species, combination may be carried out, most preferably the polyculture.
• The desirable stocking rate is 7000-9000 fishes per hectare.
• In a monoculture pond, the stocking rate is the same as the stocking density because there is only one kind of fish. There is enough food and room in a pond for a particular number of fish.
• Good growth of fish depends upon the right number of fish cultured in the pond. The stocking rate depends on the volume of the water and on the oxygen balance of the pond rather than the size of the pond.
• The ratio of fish to the volume of water should not be less than 1 fish to 2 m3 of water where there is no forced aeration.

Polyculture of carps with chinese carp

• As far as possible each pond should be stocked with silver carp and catla, the surface feeders. This should not be more than 30 to 35%, otherwise it would affect their growth adversely.
• Rohu is a column feeder and it should not be stocked more than 15-20%.
• Bottom feeders such as mrigal and common carp together can be stocked to the extent of 45%.
• Availability of aquatic weeds in the pond decides the stocking density of grass carp. It should preferably be about 5-10%.
• Rearing of fingerlings to table-size fish may continue for one year or only 6 months.