Jay, I remember you were doing that. I bought some really fine reef sand, I cant remember now the name of it! I loved it, but I rinsed and rinsed and rinsed it. lost alot of it due to it being really fine, I got tired of the rinsing so i rinsed the rest of it not as much, OMG my tank was a milky color for about two weeks, and never cleared up. I too had the white film all over the rocks, but I took it out and put in live sand instead, it is really fine too, but is already rinse and you just put it in the tank. I wish now though that I would have added the live sand to the top of it , but then as much as my sand sifters move the gravel, it may never have cleared up. but then maybe they may have cleaned it out, who knows now! I wish I could give you better advise. This was my only experience with the problem you are having now. I bailed. Maybe try the siphoning it first, that should take the milky stuff out of the sand. but dont do all of it at once, you dont want to disrupt the whole sand bed due to the good bacteria that has started to set in. maybe do in in portions one week and them do the other part the next.