Abstract: A fluid agitating apparatus includes a housing having an inlet at an open lower end thereof, and an outlet at an open upper end thereof, with a flow passage disposed through the housing communicating the inlet and the outlet. The flow passage is preferably circular in cross-section and has a minimum diameter at a throat thereof. The diameter of the flow passage increases continuously from the throat toward both the inlet and the outlet. A vertically upward directed nozzle is located in the flow passage below the throat for inducing flow of fluid from a body of fluid in which the housing is submerged into the inlet and upward through the flow passage. A tangentially directed nozzle is disposed in the flow passage above the throat for inducing a swirling flow in the fluid flowing upward through the flow passage. This creates a swirling vortex type flow exiting the outlet of the housing which provides agitation of the fluid in which the apparatus is submerged.