HELP! Low ph despite adjustment

[Trevret]

Hey guys, any advice on why my runoff PH is still reading at 5, despite the fact that I've now repeatedly brought the PH of my nutrient solution as high as 8 to try to balance it out? It's a soil grow, never had problems with PH until started feeding. Using Medi One one part system, with some cal-mag and Miracle Harvest. The Medi One brings the water PH immediately down to 4 or below, which I then bring back with PH Up. Today, for example, I added PH Up until it read a PH of 8; watered with the solution, and tested the runoff, which reads 5. I cant seem to get it up from there. Should I mix up a high ph water solution and water again? (I just watered/fed 3 hours ago). Now, its important to say, I've seen NO ill effects on my plants; I'll include a couple photos here; they're Hindu Kush Autoflower and 31 days old today. I've read a couple posts that said not to worry so much about PH in a soil grow. Anybody second that? Or is it bad advice? Any thoughts/suggestions? Thanks!

[Sww]

Adding highter ph solution probably won't higher the riz root zone ph in soil. Better adding lime or calcium to rise your pH 5. Why acid loving plants are call lime haters. 🙂

[Trevret]

Thanks Sww, how do you suggest I do so? I did add cal-mag to the nutrient solution which, obviously, had no immediate effect; should I add a separate "cal-mag only" feeding or just keep adding cal mag to the regular nutrient solution with each feeding?