PoolRx 4-Pack Black Booster 6-Month Swimming Pool Algaecide, 1 Booster Tablet Treats 20k-30k Gallons Original Formula Pool Algae Control

Additional minerals enhance the effectiveness of the PoolRx unit Eliminates all types of pool algae Reduces overall chemical demand for pool maintenance Effective for up to 6 months Suitable for chlorine, salt, UV, or ozone pools