I knew this would grab your attention - DSB seems to be like a red rag to a bull in many forums. My decision to use one in my new 6' tank was based on continual nitrate problems i had in my 2' tank previously. (Yeah, I know there are lots of other considerations). Anyway, I read as much as i could about improving nitrates and was heavily influenced by Ron Shimeks philosophies (I've probably lost half of you, my reef friends, by this point). I nearly orgasmed when I took my first nitrate reading in the DSB tank, but I am noticing a lot of crap building up on the surface of the DSB, which makes my nice white reef sand look awful. Lord SHimek says not to vacuum, but i like white sand! what to do?!?!?!?