Fish Feed Machine Knowleagde

In the rearing of catfish one of the challenges the farmer faces is high mortality rates both for those using surface tanks (block pond, plastic tank etc.) or earthen ponds. For farmers that purchase fingerlings, these losses can be crippling to their business and this article shows how to reduce these losses.

Fish Mortality is usually highest when the fish is initially stocked during the fingerling stage (< 10g in size). I have had situations where I stocked 5,000 fingerlings in a singular pond only to come back after about a month and find out there is only about 3,500 left.

HOW TO REDUCE FINGERLING MORTALITY
Do not Over stock Fingerlings in a pond
When fingerlings are overstocked in a pond, mortalities tend to be higher. It is more difficult to manage them when they are overstocked since large quantity of feed would need to be given to the fish and their subsequent waste released into the pond woudl quickly degrade the water quality which could lead to mortalities. Also, there would always be uneven growth as the stronger fish tend to feed better and grow faster leading to them preying on the smaller ones.

Sort Frequently and remove the larger size fish
Catfish are carnivorous. The larger sized fish usually prey on the smaller ones swallowing them whole. When stocking fingerlings, always try to sort them frequently (weekly), removing the quicker growing fish (shooters) and always try to put the same size of fish together.

Stock grow-out ponds at the right size
For both surface tanks and earthen ponds stocking them at the right size in the grow-out ponds determines the survival rates. Its usually best to always stock fingerlings and manage them in smaller tanks before transferring them to grow-out ponds. Given below is a table showing the expected survival rates for fingerlings stocked at different sizes and the expected survival rates: 50-100 6-20h