Sounds like you've got a good hold on things. PPM's might be a little high, but I dont know about those nutes. I used fox farms and in veg I was at 400-500PPM, but Im thinking your PPM SHOULD be ok.. Not sure though. You mean pH down? Because your pH is going up... I didn't do it that way. I let the pH rise, and as water got lower in res, I checked ppms, fed if I needed too, then pH'd it at the end. But either way it shouldnt matter that much unless for some reason your pH H+ is touching the roots as you put it in.. Are you picking up the bucket and placing it aside while you adjust pH and such? What is temp of grow room? And what lights are you using?