hmmmm........so you figure a .3 change in PH is causing all his problems? ya this is the second thread in a row you've been on, first to answer, and you've said PH is off. A really smart man once told me that when someone at the hydro store tells you that your PH is off, thats its really code for i don't have a fucking clue whats wrong with it so just buy something and shut the fuck up. Is that whats going on here? cause your zero for two bud.
to me it just looks like a calmag problem, you know, cause he says that he's just using a tiny bit of base nutrients and no calmag in a dirt system. you know, he probably could be lacking some other micro nutrients as well since he hasn't used much fertilizer on them. I'm sure you were about to ask what type of dirt he's using. it could be that promix "dirt", or that coco "dirt", or sunshine "dirt", or maybe its from his back yard and made up of dog crap and sand from his old sand box cause that sand box grows good weeds all year long. i mean honestly who the fuck phs a soil grow anyway unless their way off? nutes usually buffer the water to a useable ph anyway where I'm from most of the time. unless your adding a pile of silica to the mix and then you might need to reach for that ph tester.