over on IC i have followed a number of threads where those STG's were used in this system and every single grow was a failure, first month or so of veg they looked dynomite and these guys tried everything, end result was they all believed that it was always too soggy at the bottom and dry up top, STG's youtube demo says if you have these issues to raise the insert itself 2 inches with pvc, i seems as if that standing water effects the drainage after a while, stg;'s other products are very good i have heard, hydroton imo is the very best , i know its the worst to prep but unlike coco and perlite where you would probably have to flood less times daily, the delievery of oxygen through the clay pellets is unmatched, actually the more daily floods the better IMO simply because the drain cycle will vacuum more O2 into the root zone more regularly, what do you guys think of my theory??