A 3 X 2 factorial design of three dietary protein levels (25, 30 and 35%) and two levels of energy (18 and 20 MJ/kg) in three replications was conducted to investigate the proper dietary protein and energy levels for the growth of hybrid red tilapia, Oreochromis nilotics X Oreochromis mosambicus. Eighteen net cages (100 X 40 X 100 cm, L X W X H) were
stocked with 10 fry of fish weighing 0.4 g/fish and fed to 16-weeks. No significantly differences (P>0.05) in final body weight, gain and specific growth rate were observed among fish fed diet containing different energy levels. However, at the dietary protein level of 25 and 30%, growth performance parameters were improved as dietary energy level increased from 18 to 20 MJ/kg. The improvement of growth, feed conversion, nutrient efficiency utilization were achieved with the diet containing 30% protein and 20 MJ/kg diet corresponding to P/E ratio of 15 g/kJ. Moisture and lipid contents were affected by dietary protein levels not by energy levels. Fish protein content tended to increase as protein level
increased in the tested diets.