A process is provided for both removing and controlling biofilms present in industrial cooling and process waters. The process provides a composition which includes the reaction products of an amino base, a formaldehyde, an alkylenepolyamine, and the ammonium salt of an inorganic or organic acid. The composition may be used to remove existing biofilms from process water equipment. Further, lower maintenance dosages may be used to maintain the equipment in a substantially biofilm-free condition.