The infrequent or improper introduction of biocides into a plant cooling system may make fouling within it worse, by creating thick biofilms that can foster corrosion, reduce heat transfer, and increase water pumps' operating costs. At the other end of the spectrum, overuse of biocides can waste expensive chemicals. Optimizing the quantity, frequency, and type of dosage can improve both the health of a cooling system and its plant's bottom line.