Smith's Green CleanSmiths Green Clean Pro is a biodegradable non corrosive liquid cleaning and etching solution developed to prepare a mineral based substrate, such as concrete, brick, pavers, stone, etc., by cleaning off dirt, grime and soluble salts from the pores and surface along with producing a moderate surface texture. Concrete treated with Smiths Green Clean Pro results in a neutral pH by simply pressure washing or flushing with water per application