Five Star Chemicals has a twofold approach; the brewer first uses Powdered Brewery Cleaner to remove deposits from equipment and then uses Star San a professional grade soaking sanitizer to sanitiz e the cleaned equipment. Both PBW and Star San are safe for limited contact use with stainless steel plastic copper brass and ceramics and are safe for septic systems.Liquid PBW is a buffere d alkaline detergent that has been proven to be more than an effective substitute for caustic cleane rs. Because of its unique formulation of buffers and mild alkalis it is safe on skin as well as sof t metals such as stainless steel aluminum and on plastics.PBW uses active oxygen to penetrate carbon or protein soils and is not affected by hard water. The oxygen also helps in reducing B.O.D. and C.O.D. in wastewater which is an added environmental benefit. The concentrations to remove the se soils are typically in the 1% range.However due to soil and water conditions this concentr ation will vary. To help in hard water areas P.B.W. has been formulated with enough chelators to tol erate hard water over 17 grains. P.B.W. is an excellent choice as a soak cleaner because it does not require excessive heat as do most caustic-based cleaners. This product has cleaned brass and copper filters and industrial aluminum surfaces successfully.Use 1 to 2oz per gallon of water at 50° -170° F. Soak for 15-20min (the hotter the temperature of the solution the less contact time is need ed. The colder the solution the longer the contact time needed.) Rinse with the same temperature of water used to clean for 1-3 minutes after use. For critical applications sanitize after use.