Oxygenation of a fluid

Method and apparatus for producing an oxygenated fluid. In accordance with various embodiments, a flow of pressurized fluid is established. A flow of oxygen is injected into the flow of pressurized fluid to provide a fluid/oxygen mixture. The mixture is passed through a venturi assembly in the presence of a magnetic field established by an adjacent magnetic assembly. The mixture is next flowed from the venturi assembly to a gas/liquid separation tank, where a liquid component of the mixture is passed downstream with a selected dissolved oxygen content and a gas component is directed back for injection into the pressurized fluid flow.