The present study deals with the effect of different concentrations of EDTA (0 g EDTA/l as a control, 0.1 g EDTA /l & 0.3 g EDTA /l) on the growth in length, growth in weight, survival rate, length-weight relationship, condition factors and growth performance of the cichlid fish, Oreochromis niloticus fry reared in glass aquaria. The improvement of fish fry development obtained by EDTA is dose-dependent. Fry obtained from high concentration of EDTA (0.3 g EDTA /l) showed higher increase in length, weight and survival rate than those of low concentration of EDTA (0.1 g EDTA /l) compared to control. The growth of fish fry exposed to high concentration of EDTA (0.3 g EDTA /l), is nearly isometric.  The b value is nearly ideal (2.92) and the correlation coefficient (r) is statistically highly significant (0.99). While, the growth of fish fry is negatively allometric, in fish control(2.77) and fish exposed to low concentration of EDTA (2.43). The b value is less than the ideal. The values of condition factors are equal and the values of relative condition factors are slightly differences among fish fry exposed to different concentrations of EDTA. The total weight gain, average daily gain and specific growth rate of O. niloticus, fry improved with the high concentration of EDTA compared with the fish exposed to low concentration of EDTA and control. The best feed conversion ratio (0.66) was recorded in the fish fry exposed to 0.3 g EDTA/l compared with the fish control (0.8) and fish fry exposed to 0.1 g EDTA/l (1.02). In conclusion, the growth performance of Nile tilapia, Oreochromis niloticus fry are good pattern in the fry treated by 0.3 g EDTA /l. These observations suggest that, the exogenous treatment (0.3 g EDTA /l) may have practical utility in the fish culture.