Reading and adjusting PH of Soil through your run off

[MJCanada]

Can somebody confirm this.

If I PH my water going in, let's say it's 6.5
My run off reads 6.6.

I assume my soil PH is higher than the PH going in, as the PH had to climb because of what it mixed with going through the soil.

Is there a general rule of thumb about what the soil PH is?

Something like
PH(water/in)+ 2*(PH(water/in) - PH(runoff/out)) = PH(soil)

The above assumes the run of would test exactly in the middle of the water in, and the soil ph.

6.5 + 2* (6.5 - 6.6) = 6.7

My soil is roughly 6.7?

(didn't test the equation for if run off is lower than water in... I think you have to - the 2*(in-out) if in > out)

If my soil comes in above 6.8, I'd want to pour water(or nute mixed water)in at 6.5 to bring it down to within 6.5-6.8(cause this is soil). I also assume you do this slowly unless you are flushing because of a lockout or some shit.

 

[a senile fungus]

Firstly, pH isnt a linear scale, is logarithmic, so, pH of 6 is ten times more acidic than pH of 7, and so on and so forth.

Next, why are you worried about runoff? You are noticing an issue or chasing ghosts?

 

[Cre5cendo]

I was told to meter the water coming out from the bottom.

 

[MJCanada]

Not chasing ghosts. Just trying to understand how each piece of the puzzle works and fits together.

Ensuring your water us PHed properly is a big deal. Soil PH is a big deal. I am trying to understand how to read/measure/react to the quantitative observations as the qualitative is what takes experience.

 

[whitebb2727]

I was told to meter the water coming out from the bottom.

Nope. Check the soil itself. Checking runoff will have you chasing your tail.

Ph swim as soil dries. As organic matter decays it produces ions that buffer ph. If its a good soil it will buffer on its own.

 

[MichiganMedGrower]

Checking runoff regularly and the same way to collect the sample is useful to monitor ph and ppm trends.

It is not accurate to the ever adjusting root zone but it does show you when you are fertilizing too much or the plants may have root problems and the medium is going acidic.

It also reassures that things are going right.