I recently installed a Pentair FNS plus 48sqft filter and a 3/4HP Whisperflo pump. I get DE at the bottom of my pool though. I took the filter apart and inspected and cleaned the grids. All seemed OK so I weighed out 4.5lbs of DE and recharged the filter but still getting DE in the pool. It's a small amount though, it doesn't blow out of the retruns or anything like that and the pool water itself is clear. Any suggestions on how to clear this up? IS the filter on my Blue Diamond fine enough to trap the DE? I put it in and it picks it up abut then it returns later. I'm thinking the Diamond may stir it up but not actually trap the DE.