No access to a manual vac head so you can vac to waste? Have you brushed the last few days - especially the deep end? When you add the DE, you should see the pressure go up 1psi. Then let the filter do it's job. Don't backwash until the pressure rises another 6-8 psi. The dirtier the filter the better it cleans, that's why we add the DE - it's "dirtying" the filter in a sense. IF you backwash to soon, you've backwashed out the DE and it doesn't do what its meant to do. Hope that makes sense? You are almost there - keep it at shock level till clarity is achieved and try not to back wash. Until the pressure coming out of the returns is reduced, you shouldn't have to backwash... if your pressure/flow isn't changing then its not filtering out the gook. Keep at it for another day or so... then you can try traditional clarifier (if you like, but that's up to you.)