LW in my 6 years of experience I've noticed no difference in rate of growth or yeild between 5.5 and 6.5 PH. Nutrients remain in total solution throughout this range. I've tried both (6.5 and 5.5) from start to finish and they are the same in my experience. Bleach does nothing to release bound minerals, in fact it can increase toxicity even when well rinsed. LW I'm a chemist by trade and the advice you are giving may work for you but is in fact not correct. You seem a nice person I'm sure you mean well. Chances are this persons problems are caused from toxic salt build up in the media.