Our water polishing pads trap very fine debris and can clog up quickly depending on how they are used. Placing your water polishing pad below another filter pad like our Classic Bonded Pad where water flows through the Classic pad first, then the polishing pad can last up to a 1 to 2 weeks before cleaning is required. With that said, a polishing pad used alone can clog up as quickly as 24 to 48 hours. You know it is time to change the pad when you see water flowing around the pad not through it