its so funny that none of you guys are hydro growers and are sitting here throwing shit darts at each other to show who is right and wrong. both of you need to go to your soils and take your medication instead of giving shit advice. If you read properly and had any understanding for hydro than you would understand that he said "he had his ph to low before he figured that it needs to be at 5.5/6
The older leaves show deficiency but the new growth is doing good. So, he actually is doing good right now and by telling him he needs more cal/mag and this or that then you are causing his plant to get problems. so keep your sarcastic comments to yourself and if you can't respect one or the other then move the fuck along!