The PoolRx Blue Unit is a highly effective pool cleaner and chemical treatment for swimming pools. Designed for pools ranging from 7.5k to 20k gallons in size, this unit contains a proprietary blend of minerals that continuously and effectively eliminate algae. The specially treated alloy cylinder is packed with PoolRx+ granular formulation, which immediately dissolves and forms a stable residual throughout the pool water for up to 6 months. This treatment not only eliminates algae but also increases the effectiveness of low levels of chlorine, making it more active and productive in the water. Additionally, the minerals in the unit are rejuvenated every time they pass through the cylinder during the filtration process. Keep your pool clean and algae-free with the PoolRx Blue Unit.