I just used Red Slime Control, for about 160 gallons yesterday. I lowered the water in my sump drastically, just enough so it is skimming moderately wet. I had 4 of the K14s in my tank, but I just added 3 K4s as well. I don't siphon, I just wait until its nasty and then flip the sand over on it with my scraper. So far today i do not see anything new. I also have a phosban reactor which will be getting hooked up today using the BulkReefSupply FOxide. It's been hell since migrating from the 75, but now that I barely have any fish, I think I will be able to kick it in the pants. I've overdone CPE before and it did nothing, which suprised me as before it seemed to work wonders. From the looks of it, I am past the peak, but you never know because the affected water so slow to change in larger tanks. The Red Slime Control has never tanked my corals. I switched from using CA and Kalk reactors and have gone to 2part after seeing how much growth Bernie was getting. It's a slippery slope!