The aim of the present paper is to present the results of a study on the impact intensive carp (Cyprinus carpio L.), feeding with extruded commercial feed has on the quality of cooling waters. The feed studied had varied fat and carbohydrate contents. The study also revealed the optimal hydrochemical conditions of cooling waters for carp farming. Cage farming caused growing loads of organic matter, nitrogen, and phosphorus in the water. Experimental extraction of feed from the water revealed that high fat fish feed was more stable in comparison to high carbohydrate fish feed. Intensive carp farming with these two feeds led to considerable fish weight gain in both feed groups, but the weight gain for the carp fed with high fat feed, in comparison with that of carp fed with high carbohydrate fish feed, was significantly greater (p<0.01).
