Fresh Products Concentrated. Just toss into grease trap every 15 to 30 days, after initial cleaning. Biologically digests grease and prevents its unpleasant odors. Each dissolving block slowly releases billions of enzymatic spores that feed on grease. Enzymes multiply until grease is consumed. For use in fast foods and institutional/industrial grease traps. Results vary based on water flow, water temperature and food types. Use one block for every 40 gallons.