Effect of the self-purification of Oum Er Rbia river on the elimination of fish releases

Fish farming is a rapidly growing production worldwide, where it covers nearly 50% of fish inputs for human consumption. Releases to the natural environment are also an important issue, especially as they are visible and quantifiable, being emitted directly into the water. The physicochemical analyzes of the various Oued Er-Rbia points (ES, P1, P2, P3 and E4) show that the physico-chemical quality of the water downstream of the OumEr-Rbia magnification station shows no signs of deterioration of the receiving releases. Fish farming effluents are known to deteriorate the quality of freshwater and the excessive presence of nitrogen and phosphorus in the water leads to eutrophication of the environment. This is not the case at the Oum Er-Rbia station, but it is crucial to develop food formulations that cause the least amount of nitrogen and phosphorus released into the environment.