Need help interpreting pH test results

Finally got me a pH pen... one of those Milwaukee ones.

First, I calibrated the pen to 7.0.

Then, I tested the pH of the plain water I use. It tested between 7.8 & 8.0.

Then I water the plant with this water and captured the first runoff. It tested between 6.7 and 6.8.

So... what does this mean? Do I need to pH down my tap water or what?

Thanks in advance.

P.S. I guess I still need to do this same test but with nuted water, ya? It just wasn't feeding day today...

after you add nutes, ph. if you're in soil, ph to 6.5.

Either you didn't really answer my question or I don't understand your answer. Please explain.

all right wbd,What growbot means is, do your ph after you ad your nutes never b4.
and how long do you let your water stand b4 you ad nutes.And if you are in soil your ph wants tobe 6.5 to 7.0 should be ok with that.Hope that helps good luck with your grow m8

when only watering,, yes ph your tap water everytime, to adjust,,, when adding nutes,,, mix your nutes with water,, then check ph levels as your ph levels change due to nutes being added,,, does this help or did I get a little long in the tooth.........

I get that nutes will change the pH of the water.

I don't do anything to adjust pH at this time. To be honest, the plants really don't show any signs at all of pH or nutrient problems, and they are in week 6 of 12/12.

What I'm trying to figure out is... if the water going into the soil is 7.8 - 8.0, and the water coming OUT of the soil is 6.7 - 6.8, this would imply that the pH of the soil is lower than 6.7... probably in the 5.5 - 6.0 range, since the pH of the runoff water is the result of the tap water being adjusted by the acidity of the soil. Is this right, or am I way off base?

If that is right, then it seems to me that my soil is too acidic and needs to be adjusted slightly.

Again, plants are not showing any signs of problems... but just got this pen and I would consider making adjustments if they are warranted.

If you have gone this long without a pen and thay seem ok dont worry to much just keep doin what you are doin as things seam ok to you.If i was you for get the pen till next grow. good luck m8

Head Weeder said:

If you have gone this long without a pen and thay seem ok dont worry to much just keep doin what you are doin as things seam ok to you.If i was you for get the pen till next grow. good luck m8

Click to expand...

thanks man, that's what I was thinking too... I learned early on that over-correcting is the biggest way to fuck up a grow. If it ain't broke, don't fix it.

However, I'd still like to understand how to interpret these results at this point, just for future reference. So if anybody can clue me in, I'd still appreciate it.

and yes,, that does sound correct to me, that, if your runoff is around 6.6-6.8 and your watering with 7.8-8.0, I would be inclined to beleive that your soil is lower than your runoff..........

WBD,,, you logic sounds CORRECT...

BUT DO NOT MAKE CHANGES if your GROW IS GOING FINE... at least nothing major...

How old were th plants when you flowered?

(for soil grows)
I ask, because, plants that are flowered early in there life, 21 days or less of vegging... are far less likely to get PH issues.. even if the pH is way off... i am not sure the exact reason for this.. but i have plenty of experience and have noticed this...
FOR EXAMPLE
Miracle Grow soil causes a lot of problems for growers... except for people who flower early.... the MG soil is usually around 5.0 - 5.5 ph .. this is horrible.. but the plants seem to do great as long as they are flowered early...

cheers

Gk, I went 12/12 on day 37.

Again, absolutely no signs of deficiences except for slight and infrequent yellowing/browning on bottom leaves which I consider to be normal. Plants are very green and very healthy. Tops are 100% green which I'm impressed with considering they are past the halfway point for flowering.