ProTeam Polyquat 60 is an algae preventative for hard-to-kill mustard, black, and blue-green algae types. This product is non-metallic and non-staining. It also reduces sanitizer consumption and is not affected by high chlorine residuals. Proteam Polyquat 60 promotes sparkling blue pool water. This algaecide is highly concentrated. Best of all, Polyquat 60 is made right here in the USA to ensure the highest quality, allowing you to buy with confidence.