HASA is the purest, strongest, fastest-working liquid chlorine available. HASA has been helping save the environment for over 50 years. HASA Algi Control and HASA Algi Control Concentrate are outstanding algae growth depressants. HASA-cide should be used to control the growth of algae in your swimming pool. HASA Tile Brite may be used on all tile and porcelain surfaces in the swimming pool and in the spa to remove the buildup of oils, soaps, and mineral deposits. At 50 years old, HASA is the oldest company with the continuous use of a recyclable product.Pool Peeps commit to use to the purest, strongest, fastest working liquid chlorine available while trying to protect the environment. By using HASA recyclable products, we are saving millions of tree from becoming cardboard.