I had my filter cleaned recently. I noticed a very small leak in the tank seal after the tech left. I really wasn't too worried about it. However, after a couple of days, my pump started cavitating and would not pressurize. Pool company came back out and re-cleaned the pump. There were small (sunflower size) beads of DE clumped inside the filter and said it was due to chemicals I had added and that was reason pump would not work properly. Filter was not dirty but after cleaning pump is fine. Could it have been the small leak and pump cavitating that caused DE powder to clump?