Hasa 15601 1 gal Industrial Use Mini Bulk Muriatic Acid 14.5% - Hasa Muriatic Acid is a strong inorganic acid, also known as hydrochloric acid. It has a wide variety of industrial uses but around swimming pools and hot tubs, it is most commonly used to lower pH and alkalinity. Hasa provides products that deliver clean, healthy water for every aspect of everyday life.