How do you clean mastercool pads?

Take out the pads and soak them in white vinigar. Alkaline in the pads and white vinger have a chemical reaction to each other after the pads have soaked for a while, depemnding on how much alkaline needs removed take the pads out and either rinse them as thouroughly as you can or reinstall them and run your pump only for a few hours as you would for new installation.