yea, thats what i was thinking, and my sump is starting to develope a layer of skum on the bottom... all my readings are spot on perfect (as far as i can measure/tell) for now, its almost like its just a layer of dust that has setteled down there, my sump is glass bottomed, no substrate, thats in the fuge and the DT...
so i'm thinking that they might clean up in the sump some, but i'm worried about them getting sucked into the skimmer pump or something and messing that up, or even getting sucked into the return pump, chopped up, and fed to the fish in the DT....