Use to clean and prepare old or new concrete block, brick, poured concrete, stucco, stone, and tile walls prior to painting. Properly prepares surface prior to painting by cleaning and etching the surface. It removes and neutralizes salt-like, powdery deposits (efflorescence), mortar stains, and oil residue from forms. Just add water and stir. An alternative to muriatic acid. Coverage: 12 oz. will cover approximately 300 sq. ft. when mixed with 1 gallon water; 150 sq. ft. with 1/2 gallon water.