The replacement UV bulb is an essential part of the Pressure-Flo filter, the UV breaks down the cell wall of algae that makes its way through the filtering process. By breaking down the algae it reduces green water. Its important to replace the bulb every 1 years, the Pressure-Flo filter has an indicator to suggest when to change the bulb.
11 W Bulb - Used in the Pressure-Flo 3000 and 6000
18 W Bulb - Used in the Pressure-Flo 10000
24 W Bulb - Used in the Pressure-Flo 14000