Frog 90-Day Algae BarrierFrog 90 Day Algae Barrier is a copper based algaecide that prevents black, green, and yellow algae in swimming pools while significantly improving the clarity of pool water and filter efficiency. This product provides up to 90 days of algae prevention and is compatible with chlorine, bromine, salt generators, UV, or ozone with no effect. It also uniquely contains 4 distinct stain inhibitors to protect pool surfaces. The 90 Day Algae Barrier is