Abstract: A powdered metal oxide such as manganese trioxide, ferric, copper and nickel oxide is positioned in a tank. The tank receives a quantity of effluent that is to be rendered inert by ozone gas that is injected into the container. The oxide acts as a catalyst, in that the amount of ozone otherwise required to oxidize the fluid sufficiently to kill the bacteria and render the fluid inert is substantially reduced. The metal oxide may be utilized in the form of a powder contained in fabric bags, disposed on substrates in the tank, or dispersed within the fluid.