why adjust the pH every other day

[Mark]

Hi Ron, I have a Power-Gro drip system and an aeroponic system that I built myself, both using gro-rocks. I use Rockwook Formula One A+B nutrient solution with a drop of SuperThrive per gallon. My problem is that after a week I have to adjust the pH of each system like every other day because it starts to become acidic, like around 5.0 or slightly lower. Is this normal? I have another system that uses the same nutrient solution, and the only difference is that I don't use gro-rocks. Aren't gro-rocks suppose to be inert as far as the pH is concerned? But it is the only difference, and I use rockwool and the roots dangle in solution aerated with a air stone. Will having to adjust the pH constantly affect the growth of my plants? Or is it ok as long as it doesn't drift too far acidic. Thanx for all your help, Mark.

[Ron]

Not adjusting your pH would have more of an effect on your plants growth than constantly raising the pH. I would keep it at 5.5 to 6.5 no matter how many times it took.