598787 Disclosed is a process for treating with at least one chemical compound a body of water comprising at least one living organism selected from fish, molluscs, crustaceans and aquatic plants. The process comprises adding the chemical compound to the body of water and agitating the water with an agitation system comprising a pump and at least one submerged outlet equipped with an eductor nozzle. The eductor nozzle comprises a nozzle part through which exits the liquid pumped through the agitation system via the pump, an eductor part through which part of the water present in the body of water to be treated is sucked, via at least one suction opening, the flow of liquid being called induced liquid, and a diffuser part in which the pumped liquid and the induced liquid are mixed and exit from the agitation system in the form of a total outlet flow. The induced liquid is drawn in the eductor part and then in the diffuser part of the eductor nozzle due to the high velocity of the pumped liquid exiting from the nozzle part of the eductor nozzle. The total outlet flow exiting the eductor nozzle is from 1.5 to 10 times greater than the pumped liquid flow rate exiting the nozzle part of the eductor nozzle.
