implementation of acceptable limits or acceptable zones of
effect over a defined timeframe [2]. The aim of this paper is to
evaluate the impact of fish cages on water quality and to find
out the possibilities to reduce negative impact of the fish
farming on farming location. The temperatures, oxygen
content in the cages and out of the cages at different depth, at
different time and at different distance from the cages were
measured. The content of nutrients, added food, horizontal
and vertical profile of chlorophyll a was analysed. The
correlation between temperature, food supply, nutrients
content, oxygen content, and primary production at given time
and space scale were obtained.