Abstract: A device for destratifying bodies of water for controlling water quality parameters. The device includes an elongated hollow shroud within a cylindrical pipe that is capable of being supported in a vertical position within the body of water. The shroud is mounted on a center hollow drive shaft. A reactive propulsion driven rotary arm disposed in the plenum of the shroud is driven by pressurized fluid. Within the pipe, but outside of and near the lower end of the shroud's drive shaft, an impeller forces water upwardly and axially around the shroud to the water's surface. The reactive propulsion means is preferably driven by pumped air, whereby the effect of the pressurized air rotates the arm and the impeller fixed to the common drive shaft. This action aids in destratifying the body of water. A series of guide vane blades may be interposed on the same drive shaft between the impeller and the shroud to reduce the turbulence of the water exiting from the impeller.