The invention is a composition and method for treating paint booth water systems to facilitate paint removal. The composition comprises water, solid particles of insoluble organic polymer, such as, by way of non-limiting example, urea methanal copolymer, preferably including less than 50 weight percent of particles of diameter of 1 micron or less, and optionally surfactants, thickeners, polymeric flocculents different from the organic polymer, clarifiers, anti-corrosive components, and/or biocides.