Effects of food ration on growth,condition factor,food conversion efficiency,and net yield of estuary grouper, Epinephelus salmoides Maxwell,cultured in floating net-cages

The effects of food ration on the growth and yield of the estuary grouper raised in floating net-cages were investigated. The optimum ration given on alternate days was 5% body weight (wet) which gave the best mean fish weight, uniform condition factor with time, relatively good survival rate, and greatest efficiency of food conversion. The maintenance, optimum and maximum food rations were 1.41, 5.75, and 9.0% body weight (wet) respectively. The fish were more uniform in size when fed 5–8% body weight. Though the yields at the end of the experiment were higher with high ration rates, the difference between rations of 5 and 9.1% body weight was 26.8 and 33.6%, whilst that between 5% and 2% body weight was 596%. For economic production, the ration should be approximately 5% of body weight supplied every 2 days.