DE in the spa??

[mshumack]

If you over fill the filter with DE powder it will dump some out in the pool. The problem with backflushing the filter and adding fresh DE is that you can never know how much DE was lost during the backflush and how much to add, It's too easy to over or under fill.

That' why I always dissasemble my filter and completely clean/empty and refill whenever the filter shows signs of being clogged. Fortunatley, it's only two or three times a year (on a year round pool).

Looks like you will have to disassemble yours for inspection - but if you don't see anything wrong (torn) you probably just over filled it.

[Pool Clown]

Ways DE can get past the filter, i.e from the "dirty side" to the "clean side":
1 It can get past an o ring or spider gskt in the B/W valve. Or crack in the housing.
2 You can have a hole/rip in the fabric that makes up a grid. Or the grid can be blown out of place in the grid bundle, if the bundle has gotten loose.
3 There is a certain amount that can get through the internal air bleed, but this will be negligible if you have the screen on the tip of the bleed tube.

mshumack:
I have never heard of a filter "filling up" with DE, and by-passing the overage back to the pool. How does this happen? How does the filter know when it has had enough DE? And how does the DE get by-passed through the filter when the overfill is happening? Please elaborate, I want to know more.