Newbee Grower: Ph lesson learned

Howdy all

I am a newbie cannabis grower started this year, but I have been gardening all my life. Although I have never paid much attention to ph for gardening I used the city water, through my readings prior to growing I realized Ph was an important aspect of growing as was water quality. No more straight city water.

As I am only growing for personal use (2 people) my water usage is minimal so I purchase Crystal purified water from the machine outside my Safeway grocery store $0.25 per gallon. I have a bunch of 7 gallon water containers for camping which I use for storage. I also have a bunch of 1 gallon bottles that I use for mixing.

Based upon my reading I needed Ph for soil growing (switching to coco for next grow) in the low to mid 6 range. The Crystal water Ph was a little high so I used white vinegar to lower the Ph to that range. I then used that water to water AND mix my nutrients in, using Fox Farms Trio for soil.

I was advised by someone who grows professionally that using vinegar will change the Ph but that over time it will revert to the original Ph. I did a test with 1 gallon of water and found that the Ph remained stable for at least 4 weeks so I don’t mix more than I am going to use in the next few days.

While reading about Coco growing medium I read for the first time to check the ph AFTER adding the nutrients and adjust the Ph then. This should have been obvious but when starting out I was trying to carefully follow growing procedures I had read.

Anyway with the Crystal water if I want plain water I have to add 35 drops of vinegar to each gallon of water (Ph starts in the 7+ range) BUT if I want my nutrients solution to be the proper Ph I need to raise the Ph of that same water significantly after adding the nutrients to achieve the proper Ph as the nutrients mix has a Ph in the low 5’ possible upper 4’s. Currently I don’t have a Ph testing tool that goes below 6.2. Ph testing Methods suck I’ve tried a probe and I could not get it calibrated from the start. Currently using strips but changing to the Ph Up/Down system which comes with a tester which uses water and a reagent and color scale.

I have probably been stressing my plants with h2o that is the proper Ph and then the nutrients solution is really low.

Hope this helps someone and happy growing.

Now I get to see how cannabis does in 110-115 degree temps. Oh I am growing autoflowering plants.


No need to ph your water prior to adding nutrients. Wait until you add your nutrients and then ph. That way you’re only ph’ing once.


I would advise to invest in a quality ph meter. Apera and Bluelab are both dependable brands. Many of us have gone through cheap meters only to end up buying one of the mentioned brands


Definitely get a good pH meter… The Apera PH20 is a great choice! I have the PH20 and their more expensive PC60 that does other functions and the PH20 reads just as well! If you get the PH20, I would recommend getting the EC20 as well to measure your nutrient solution and runoff if you have any issues in the future, or just get the PC60 like mine and have all the functions in one meter, plus a backlight!


Bobby that was exactly my point.

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Sorry, I must have misread your post.

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Thanks for the tips on the meter, not sure I’m ready to spend 130 +/- for a meter to grow a couple of lbs a year. With that said it is good to have a quality meter to consider. First I will use the Ph up/down with it’s test kit for $18.00.

Thanks for all the responses.

The Apera 20 is just $50 i believe. Best $50 spent in years. Lol.

But love the lesson… we all… (well most of us) go thru it sooner or later. Lesson learned. And ur a better grower because of it. Keep em green


I’m pretty sure that the color chart/scale is based on water being clear . . . changes color when you add nutrients in most cases that I know of. I’ve always been told that the nutrient solution color skews the results if you use those drops.