An experiment was carried out to compare the effects of fertilizer application alone, concentrate feeding alone and a combination of fertilization and feeding on water quality parameters and growth performance and yield of Nile tilapia (Oreochromis niloticus). The treatments were weekly fertilization with urea and Di-Ammonium Phosphate (DAP) at a rate of 3 g/m2 and 2 g/m2, respectively, concentrate feeding at 5% of fish body weight and weekly fertilization with urea and DAP plus concentrate feeding at 2.5% of fish body weight. The concentrate diet contained 30% crude protein. Three fingerlings per m2 of sex-reversed Nile tilapia were stocked in the tanks. Water pH, dissolved oxygen (DO), conductivity, total dissolved solids (TDS), salinity, temperature, phosphorus and ammonia were measured weekly. Fish body weight was measured fortnightly. The experiment took 166 days. Results indicated that treatment had significant effect ( p ≤ 0.001) on DO, conductivity, TDS, nitrate and phosphorus but not on pH, salinity, temperature, ammonia and alkalinity. Fish cultured under the combination of feeding and fertilization had higher (p ≤ 0.0001) weight gain (257.37 ± 5.71 g), growth rate (1.50 ± 0.04 g/day), yield (13,128.35 kg/ha/year) and lower feed conversion ratio (FCR) (1.89 ± 0.03) than those reared under feeding alone (weight gain = 214.11 ± 5.90 g, growth rate = 1.25 ± 0.03 g/day, yield = 10,688.06 kg/ha/year and FCR = 3.35 ± 0.09) and fertilization alone. Rearing of fish under the combination of feeding and fertilization resulted into higher (p ≤ 0.0001) profit (TZS 51,692,3527) compared to culturing under feeding alone (TZS 14,422,208) and fertilization alone (TZS - 7,057975). It is concluded that the combination of weekly fertilization and daily concentrate feeding at 2.5% of fish body weight promotes higher growth rate and results into higher profit than either weekly fertilization alone or feeding alone daily at 5% of fish body weight.