It all started nigh on two months ago with some fungus gnats, which in my naivety I decided to ignore. After repotting my babies I noticed some inordinate wilting, from which they did not recover in the ordinary transplanting time frame. Suspicion fell to gnat larvae. A peroxide rinse later, the plants are still wilting, although not terribly, it isn't getting better. The leaves are yellowing beginning at the tip/edges and working inward, most significantly at the base of the plant. It's been several days; with all the adult gnats stuck to yellow cards, and all but a few larvae no doubt fried by H2O2, I feel like I should have made visible headway if that were my problem. I now believe that pH is probably to blame, as my repotting did coincide with the use of a new product, MadFarmer's N.U.T.S. The label calls it a humic acid supplement, a large part of the growing community insists that it is fulvic acid, and there seems to be some contention as to whether or not it is a contributor to pH imbalance. I'm watering with municipal out of a three-stage filter (don't bother, I know, but it's worked flawlessly for two years until this point), with Fox Farm's Grow Big, and SuperThrive in coco/perlite with Great White mycs under 2000 MH. I've run this grow several times with respectable success, and I'm at risk of pulling my hair out. The Problem: My pH meter is assy-ass, one of those two-pronged Frank's nursery deals. What I'm really after is some educated conjecture as to whether or not the use of Mad Farmer N.U.T.S., combined with what I now know to be a rather foolhardy H2O2 bath, could be causing a dangerous pH imbalance, and whether or not such an imbalance might cause the symptoms I'm experiencing. Thanks in advance to ya'll knowing-things people.