PH Question (Up vs Down)

[FredGarvin]

Howdy,

Where I live the water PH is around 7.8/7.9, which is high but I can work with. (Waiting on a ECM I ordered so no gottie yet)

From what I understand about adding nutrients is that it should raise the PH of the water, but I am having the exact opposite reaction. Once I add my nutrients the PH is down considerably.

I use (roughly) 1/2 tap (tap stands for 12 hours) and 1/2 distilled, which still gives me a starting PH of 7.25 or so. Mixing a gallon at a time, it drops the PH down to around 6.1’ish.

This is using Calmag, Dynagrow and Hydroguard for the DWC. (In Veg) For my outside plants in flower it‘s the same gig except I use Calmag, Dynabloom and Signal.

Is this normal? Is there something I am missing?

Thanks in advance for your help,

FredGarvin

 

[Bob's Auto's]

Some nutrients with lots of sulfates in them can alter the pH downwards. This is nothing to worry yourself about. Just keep an eye out for change a change when those nutrients are used because this will make your pH rise.
I would lower the pH still to 5.5 and measure every day. When it's risen to let's say 6.2 again add pH min or another acid until 5.5 and so on. A little drift in pH makes the plant absorb a wider range of nutrients in it's own optimal range.

 

[Mañ'O'Green]

Howdy,

Where I live the water PH is around 7.8/7.9, which is high but I can work with. (Waiting on a ECM I ordered so no gottie yet)

From what I understand about adding nutrients is that it should raise the PH of the water, but I am having the exact opposite reaction. Once I add my nutrients the PH is down considerably.

I use (roughly) 1/2 tap (tap stands for 12 hours) and 1/2 distilled, which still gives me a starting PH of 7.25 or so. Mixing a gallon at a time, it drops the PH down to around 6.1’ish.

This is using Calmag, Dynagrow and Hydroguard for the DWC. (In Veg) For my outside plants in flower it‘s the same gig except I use Calmag, Dynabloom and Signal.

Is this normal? Is there something I am missing?

Thanks in advance for your help,

FredGarvin

Yes your premise of nutrients raising PH is incorrect. By and large they will lower PH as you have observed. The drift allowed theory is correct but I maintain 5.6 to 6.1 as the limits.

 

[FredGarvin]

Awesome thanks guys. I learn a little more each day.....

 

[FredGarvin]

Timing is everything.... the EMC meter came and I am sitting at 671 ppm....... I have no idea if that is good or not, but looking at some posted information it seems to be in the right ballpark. Whatshould I be looking for in regards to EMC?

 

[Mañ'O'Green]

Timing is everything.... the EMC meter came and I am sitting at 671 ppm....... I have no idea if that is good or not, but looking at some posted information it seems to be in the right ballpark. Whatshould I be looking for in regards to EMC?

@FredGarvin Don't forget to measure your starting water and subtract that from the nutrient reading. If your starting water is over 200 PPM we need to talk. Be sure you are using the Hanna scale in the USA and EC in the rest of the world. Here is a handy equivalent chart.

 

[FredGarvin]

Roger that. I will be doing a full change in a week or so as we are getting close to moving from veg

However, just out of the tap it is reading 420.......... so if I am cutting that with distilled I have no idea what I am looking at.

I will revert next week. If there is anything I need to know in the interim please advise soonest.

Thank you for mentoring me Man’O’Green!

 

[Olderfart]

Tap water at 420 ppm may be bad news. If you cut it 50% with distilled, it will still be over 200, so @Mañ'O'Green is the guy to help out with where to from here. I ended up ditching my tap water altogether (it was ~360 EC as I recall) and now use stream or lake water instead, which came in at ~ 30 EC. Hard water can bugger up your nute mix.

By the way, a simple way of avoiding the EC/PPM conversion BS is to just use EC from the start. PPM can be ambiguous because of different meter manufacturers or different posters not specifying conversion rates. If you just get used to using EC, the ambiguity is gone. Sadly, not everyone posts EC or their assumed conversion, although most nute suppliers list both. I just use EC.

Oh, and one more note - when you use your meter, double check to make sure that it is in fact set to either PPM or EC, whatever it is that you are using. My meter has a nasty habit of changing its mind once in a while, and I didn't notice that it had changed from EC to PPM one time and mixed my nutes at 2X strength - it was not a good idea.

Good luck with your grow.

 

[Mañ'O'Green]

Roger that. I will be doing a full change in a week or so as we are getting close to moving from veg

However, just out of the tap it is reading 420.......... so if I am cutting that with distilled I have no idea what I am looking at.

I will revert next week. If there is anything I need to know in the interim please advise soonest.

Thank you for mentoring me Man’O’Green!

Are you on municipal water if so there will be a water quality report online Take a screen shot of the Water Hardness section and while we are at it get the sanitation section also. If you have trouble getting that to me I can PM you and get the link to the report If you do not mind me knowing where in the world is @FredGarvin

What kind of meter do you have? Is there any chance you are on the wrong scale?

 

[Mañ'O'Green]

Ok we have the water report.

They do not use Ammonia so you do not need to worry about chloramines and the chlorine will dissipate on its own quickly.

If you look at the Max Level no individual mineral is over the limits for plants - not even close. They add up to about 185 PPM so you have some really bad water lines (old) or that meter is not reading correct? In any event the practice of mixing your water 50/50 is a good idea until you can verify that meter. There are test solutions available.