Abstract: A method and apparatus for removing specific contaminants from an aqueous solution in a recirculating tank or linear treatment system is described. An aqueous solution is pumped into a reaction chamber. Measurements from the aqueous solution are collected, including one or more of Free Chlorine, Total Chlorine, Total Ammonia Nitrogen, pH, bacteria in the tank, and Oxidation Reduction Potential. In response to the measurements collected, one or more of pump speed, injection of pH precursors prior to the reaction chamber, reaction chamber electrode voltage, current, infusion rate of the chlorine, and contact time of the aqueous solution with the chlorine, are adjusted.