Clorox Pool and Spa Algaecide Clarifier Liquid is a 2-in-1 maintenance product that prevents and treats pool algae. When conditions are right an algae bloom can occur in a matter of hours. Being one step ahead of algae is crucial because as it grows chlorine must work harder to keep the pool clean. Since summer brings warmer temperatures and ideal weather for algae spread the pool is in need of extra protection. This treatment will not only keep the water blue and clear from those uninvited green pests but using this Clorox algaecide clarifier weekly can also stop the spread of algae in the future. This duo also helps the filter remove small particles and dead algae from lingering in the pool. While some algaecides help fix a current problem Clorox Pool and Spa Algaecide Clarifier combines two essential things: solution and protection both of which contribute to a cleaner healthier and more sanitary pool for the whole summer. Always apply chemicals according to label directions. Circulating pool water when applying the pool algae treatment helps disperse chemicals throughout the pool for maximum coverage.