In the present study, two hatchery strains of Oreochromis niloticus and two of O. andersonii sourced from different hatcheries in Zambia were subjected to the same feeding and management regimes in a controlled indoor tank environment. All strains were stocked at a mean weight of 2.1 ± 0.01 g and harvested after 175 days. Mean final body weight at harvest for the two O. andersonii groups was 65.2 ± 31.5 g and 73.8 ± 38.5 g, which was significantly (P