I opened my pool with a new DE filter, and have had to clean and recoat several times because of my algae problems. I've only cleaned it by flushing per the instructions, and am experiencing quick increases and slow flow back through the inlet to the pool. This is happening in as little as 15 minutes after a complete DE recharge. Do I need to open up the filter and clean it? I also have the flow control disc installed since my 1 HP pump exceeds the recommended flow for the filter. Why could I be experiencing this problem? I've been searching for an answer before I open uo my filter. This site is loaded with info, and I appreciate all of the help already!