I've been using regular IO for over a year and a half and I always mix up the bag before use. A couple months ago I got a box that mixed up to 17DKH, 680CA and took 2 days to clear up. I complained and they sent out a new box. But this new box mixes up to 6.7DKH and 480CA but at least it clears overnight. So I'm kind of over it, thinking of switching to HW-Marinemix Reefer because it's advertised to be about the same parameters I'm at. I'm using the 17DKH stuff for WCs on some live rock I've got in a brute and to hatch BBS.