ACID Magic is a full strength product formulated to replace standard muriatic acid that is easier to ship, store, and handle. This revolutionary blend of proprietary ingredients offers the cleaning and pH reduction of powerful acids while providing increased usability. USES Pool and Spa: Excellent pH down and alkalinity adjuster. Extremely effective acid wash. Marine: Works instantly to clean and remove stains, discoloration, and debris left by barnacles and algae, and stains from rust and exhaust from boat hulls. Paint Preparation and General Cleaning Construction Use to etch concrete in preparation for painting. Cleans excess mortar from brick and cinder block. Removes rust, scale, mineral build-up, and stains. Cleans vats/tanks, lines in food and beverage plants. Cleans tile and porcelain in restrooms and locker rooms. ACID Magic has many other uses, too!