ProLine® 05045 PUV-4000 Pressurized Filter System with 40W UV Clarifier 4000 gal. THE PROLINE PRESSURIZED FILTER SYSTEM features a unique, manually operated agitator that quickly dislodges waste from the filter chamber which allows you to backwash and rinse the filter in seconds without getting wet or coming in contact with fish and plant waste. Best of all, these filters never need to be opened. Available with or without an internally mounted UV Clarifier that controls green water algae.