Five species of fish were cultured separately in concrete ponds, 840 cubic meters of water per each with a water circulation system. Every species was stocked at a rate of 35000 fish seeds per pond. Species involved were Oreochromis niloticus (0. niloticus), Common carp, Mugel cephalus, Marone labrax and Chrysophrus auratus with, 28. 0 it 0.3, 12.0 土. 20, 30.5 土 0.7, 1.1 土 0.1 and 1.3 土 0.1 initial body wights in grams for each species, respectively. Samples of the same species with the same initial body wights were stocked together at the rate of 7000 fish seeds per species giving a polyculture with stocking density of 35000 per pond, Feeding rate was 574 from the stocked biomass and corrected biweekly according to the recorded average weights using diet containing 26. 57% crude protein. Biweekly samples (to about 1000 fish) were collected from each pond, weighed and the average body weights were