AquaDoc Pool & Spa Stain and Scale Control for Hot Tubs - 64oz - Pool Stain Remover that Helps Prevent & Remove Calcium, Iron, Copper & Rust Buildup - Made in USABrand: MAV AquaDoc Features: Pool & Spa Stain Remover AquaDocs stain and scale remover helps prevent and reduce stains in both pools and hot tubs. It helps tackle calcium, iron, copper, and rust buildup on surfaces and equipment for cleaner water and easier maintenance. Stain and Scale Control for Inground Pools & Hot Tubs Use as a pool scale remover or hot tub stain and scale control to fight tough deposits. It works to minimize chalky buildup and