Abstract Disclosed herein is a water treatment system for connection to a water treatment plant (e.g. a dissolved air flotation device). The plant may have an inlet for the receipt of feed water (e.g. waste water) and an outlet for the discharge of treated water. The treatment system may comprise a first sensor disposed such that it is in fluidic communication with the feed water, and a second sensor disposed such that it is in fluidic communication with the treated water. The first and second sensors may be configured to sense parameters of the feed and treated water. The system may further comprise a first applicator (e.g. a pump) that is configured to discharge a treatment source (e.g. a chemical source) to the plant to treat the feed water. The disclosed system may be used to treat waste water (e.g. the treatment of effluent from oil refineries, petrochemical and chemical plants, natural gas processing plants, paper mills and general water treatment). The system has analogous applications in other processing methods that also use DAF, or very similar, systems, such as the processing of mineral ores and other such solid extraction processing methods.