I adjust PH in my ladies .. think about this if you will. What would happens if you used one of those favorite nutrients and that shit ended up dropping your PH down around 4.5 or lower. You mean to tell me that wouldn't kill your plant, and or cause some sort of nute lockout?? lol
I'm always at 4.5-4.7 immediately after I mix my solution...and yes, plants will not like you if they are fed with it immediately-i've tried.
That initial reading of ph immediately after your solution is mixed is misleading. When I'm done making a fresh batch of nutes my ph is 4.7. If I wait 20-24hrs it stabilizes to 5.8 and stays there. If your mixing your nutrients and adjusting ph immediately that isn't an accurate reading of your ph.
If you mix nutes, adjust ph, and water the ph of your nutrient solution surrounding your rootzone will raise by the hour. If I adjust my ph to 5.8 in a couple hours it's over 6. In 24hrs it will be almost 7.
So I try to mix at least 18hrs before I use it and I don't add any ph up or down. After 18-24hrs your ph should stabilize and then it's ok to adjust ph.
This is of course in my experience. Adding any ph up or down actually screws everything up for me considering my solution will stabilize to 5.8 in 24hrs without adding any ph up or down.