PH Runoff

I water with PH 6.5 but my runoff is always PH 8.0. Is the plant getting 6.5 or 8.0 or does it end up being somewhere in the middle of those two numbers?

If my plants are ending up with water that is PH 8.0 should I be adjusting my water to a much lower number until I get a runoff of somewhere between 6.5 - 6.8?

On a side note I've been watering them this way since day one and things have been going fine for the most part but I am getting a few leaves starting to turn yellow (not sure if I'm suffering from nute lock up or not). I'm almost three weeks into flowering and they vegged for 10 full weeks.

I'm not to sure I want to take any drastic measures seeing as I only have about 6 weeks of flower left.

sounds like things have gone pretty well - 3 weeks sounds too early for yellowing though

i have the same problem, and still dont know what caused it .phed water at 7.0-7.2 and runoff is about 6.0-6.2?

maybe my question was misunderstood.

I'm feeding with water that is adjusted to 6.5 but my runoff is reading 8.0. What I am wondering is, are my plants being fed with water that has a PH of 6.5 or 8.0. Or do they end up getting something in between?

Hope that makes it a little more clear.

my understanding is that the runoff ph is closer to what the plant roots are experiencing
i use ph drops so runoff is what i can test, a good ph meter will give you the soil ph