Ph question

I have been growing in pure cocoa and my girls are about 6 weeks and 14 inches tall. Im using F F organic nutes. I learned last night after some research that I hadn't flushed nearly enough and my nutes had built up in the soil. I always water with 6.2ish ph, but my run off I found to be 5 or lower!! I transplanted to 3 gals and flushed with 6 gals per plant of 6.5 water. My runoff is still like 5.... What gives?

Do I need to water with higher ph water if my cocoa is 5?

By the way I tested some new cocoas runoff and its 6.0, so the nute remnants must be throwing it so low. So should I flush more? Water witb higher ph?

I've been having the same issues with my peat based soil mix. I usually feed at about 6.5 PH with runoff within .1 PH of that, but now I'm getting runoff at 5.8ish. To me that indicates my soil is probably somewhere in the 5.5 range. My $10 soil PH meter still reads almost 7.0 so I don't know which to believe. They are 6 weeks into veg and are nice healthy bushes and I don't want my PH to continue to drop. I added lime when I made my soil 2-3 months ago. I assumed that a flush would "reset" the soil PH to 6.5ish, allowing me a little more play room. I've got some Bushdoctor I've been wanting to try out. We are probably making a big deal out of nothing. The salts could be lowering the runoff only because the soil isn't present to balance them. Our soil may be perfect, but I don't trust a $10 tester over an experienced growers knowledge.