MrJonesanswered grow question 4 years ago I think you are on track, with POH perfect it is supposed to help manage this for you, it looks like it needs more nitrogen, that will help the yellowing, but this should be provided in your PH perfect product line, what is the growing medium I see you are saying soil, but knowing a bit more about that may help, what are you using for water, if not RO, what are you doing to remove the Chlorine and Chloramine from it, I have been growing organically, and shooting for around 6.2PH seems to be great, if my PH is high I have been using distilled white vinegar seems more natural and very very cheap, with great results.