Muriatic acid

Muriatic acid is common in pool care, and it is dangerous if mishandled. Fumes burn the nose and lungs, and the liquid burns skin and eyes. It can also damage metal and stone.

Follow the label every time. Wear gloves and eye protection, work outdoors, and always add acid to water, never water to acid. Pour slowly in front of a return jet with the pump on, and keep it away from chlorine products. Never mix them. Store it in a cool, sealed spot out of reach of children. Retest pH and alkalinity after an hour. A pro can do this for you.