Normal for DE to be in pump strainer after shutdown?

[cruzmisl]

My filter is a Pentair FNS Plus-it doesn't have a "bump" option. I only ever cleaned it once and I took it apart and cleane dit out totally. I'm going to install the check valve tomorrow and see if that makes a difference. I'm not sure if the filter itself has a check valve. I have a multiport valve if that matters.

Thanks for the help

[waste]

From what's been posted, it's probably the water from the spa causing the backflow through the system. I'd put the check valve on the spa line, it'll stop the DE problem and keep you from having to re-fill the spa every morning.

$.02 worth