This formulation was specially designed to fight tough black algae. Contains copper and penetrating agents to kill and prevent the growth of even the most deeply rooted algae cells. It allows for swimming without waiting and is compatible with all pool types. About the Brand: Applied Biochemists was developed for use in lakes, ponds, and other outdoor bodies of water. Our water care products are economical and powerful enough for the toughest jobs. Applied Biochemists offers everything from algaecides and deposit control formulas to non-chlorine shock treatments, powerful surface cleaners, and more. If you like using Applied Biochemists, check out some of the other brands from our parent company, Sigura. With brands like HTH, Leisure Time, GLB, Spa Selections, and PooLife, Sigura has a long heritage of experience in developing innovative water treatment solutions for use in pools, lakes, ponds, hot tubs, and more. At Sigura, we have an unparalleled passion, pride, and commitment to improving the environment and enhancing the security, health, and safety of the global communities we serve. With our track record of innovation and simple, intuitive solutions that anticipate needs, Sigura customers feel secure as they enjoy their pools, spas, ponds, and lakes.