ProTeam Mustard & Black Magic effectively removes all forms of algae and maintains clear swimming pool water. This product is non-metallic and non-staining. It leaves no offensive chloramines and does not contain ammonia. Mustard & Black Magic restores water clarity and has a sanitizer exciter, which lowers your consumption. Best of all, Mustard & Black Magic is made right here in the USA for the highest possible quality, allowing you to buy with confidence.