Well I checked the pool this morning and the pump pressure was holding steady at 15 psi. So, the DE is working. There wasn't nearly as much DE settled at the bottom as there was when I put the DE in. The pump only runs 6 hrs at night, so I'm figuring there was plenty of down time for the DE to settle. I keep vacuum (not to waste) and see if the DE quites settling. Do you guys think that with the amount of DE I added that some will continue to blow by the sand? If not, I'll just wait and let it go until I do my next backwash and then re-do it with a smaller amount of DE.