This is a really good thread as I have been in the same or similar situation this year. Since I have been doing BBB, never had a problem. This year, can't get the thing clear for love nor money. Now am looking to add the DE to my sand filter as well.
Regarding the DE, do you have to add it after every backwash? I backwash frequently, a few times a week, so this may not be so good.
Moderator note. This was split off this topic: Desperate -- pool party tomorrow. Cancel party? Floc? Yes, I HAVE BEEN SHOCKING! - Page 2