Gordon's, gallon, ready pour formula, Pondmaster SeClear Algaecide & Water Quality Enhancer, kills all types of algae including toxic blue green algae, controls planktonic, filamentous & plant like types of algae. Helps stop algae before it starts by reducing the phosphorus available to fuel growth, fewer applications & lower use rates are necessary when used preventatively. For use in still or flowing aquatic sites including ponds, lakes, reservoirs & potable water sources. Will not harm fish or livestock when used as directed.