Ph soil versus water testing


Can I get some thoughts on what is best Ph testing with a soil meter or I guess flushing your plants and then testing the runoff water?

And what meters do you personally use?

Googling seems to say the water and soil testers are not accurate (sorry Mac, can’t afford the digital $140 one… Wish i could)

And best way to adjust the pH (the up/down kits or lime i think)?


Using one of the cheap yellow pH pen sold on Amazon. It seems to be accurate going by testing solution.


You can buy a Milwaukee ph pen for about $10 and the self calibrating one is about $27 bucks and they work pretty well as long as you keep them calibrated and clean after testing nutrient water so the salts don’t build up on the glass eye that read the levels .


Thank you… Anyone have thoughts on soil testing versus the water runoff tests?
Or what to use to adjust the pH?


@BrockSamson testing the run will be the most accurate as it test at the soil level . General hydropics sells ph up &Down . Hammer.


Wonderful its HammerTIME! Over various sites it had been difficult to get this answer.


@BrockSamson by the way WECOME to the ILGM forum … we also have a members lounge .you can talk about anything there But Growing MJ … … hey if it looks like a nail .Who You Gonna Call …lol lol . Hammer


I just got my pH meter (yellow one) and TDS (blue) from amazon. Has anyone had good luck or bad using these? Oh also got a temp/humid digital for monitoring those. First time grower here, i plan on using potting soil and have not decided what nutrients to try. Wish me luck :slight_smile:


When it come’s to meters …i like them to have one touch calibration , auto temperature comp, …and saying a BLUE TDS dosnt tell me anything … Sorry .need more info … and one more thing ,stay away from miracle grow potting soil … go pro mix BX …you cant go wrong with it . Hammer


Lol I know exactly what pH pen and TDS meter you got, did you buy the combo pack?

Either way, I have 2 TDS meters myself, and they work great, never had a problem. Both give me the same readings, so I know they’re both accurate, or both broken in the same exact way lol

And you’ll definitely need that temp/humidity gauge, so good buy!


@Hammer Uhhh Ghostbusters?..

Oh sorry my bad


@metalcrow I’ve also been shopping for the ph meter… I think i finally have a found a one touch easy calibration (yellow as well) as hammer mentioned.

For the tds i have one of those “Zero Water” pitchers which came with a blue one. I also grow Venus Fly Traps (named Audrey II if you get the reference) it needs water without any minerals or tasty additives etc (will kill her). Distilled or R. O water is suggested but I found both Zero Water and distilled both test around the same TDS.

So i now water all my plants with zero water… 2 of 4 of my MJ seedlings have died but im fairly confident this was a lighting issue… My VFTs are doing well and this option is cheaper than buying water.

I’ve read that distilled water should have a pH of 7, a good starting point for testing and adjusting the pH…time will tell if this works and if so a cheaper / easier option than buying water at the store.


Yep Kteez420 the combo pack. Hammer thanks for the advice on the miracle grow and i’ll check out the pro mix BX, Xcellent.

Global 0.05pH High Accuracy Digital Pocket Size pH Meter Tester with
ACT & Backlit LCD and TDS-3 Handheld TDS Digital Meter with Backlit
LCD Combo, Handheld, Portable HG078


Brock is the Audrey from little shop of horrors ? thanks for the good advice all!


I collect the condensation from my AC that cools my grow room. It’s free, and tds is >20 anytime I test. Don’t know if anyone out there is dripping pure water onto the ground. Lol!


@metalcrow… Yes sir Audrey says… FEEEEED ME!


I use the water from my dehumidifier. TDS is always under 5 PPM. I also buy local spring water though, only 25 cents a gallon so I don’t mind. I drink a ton of it anyway!


A Note to Beginner’s … I do not recommend the use of the waste water Form Dehumidifiers or AC’s units … the reason is simple ,they pull a lot of air thru themselves thus concentrating any air Bourne Pollutants , into the condensation water , your using … . And One more thought Why use it at all .?Can you get a better source .Or a way to make the amount needed more economically… ? A modern R.O of 50 GPD can be had on Amazon . com … @ latewood . And a Amazon link can be found in the buyers guild … Good growing . Hammer


I tend to agree @Hammer about AC & dehumidifier water… Lots of particles and dust floating in air… Hope they have a really good air filter. Another example is Boiled water can can also be an issue from a tds viewpoint particles can remain and be reclaimed… Might be ok for us to drink any bacteria should be dead, but dead or alive what are you putting into your plants? Hope you have a quality name brand filter.

Im still up in the air on the RO systems i posted on your topic on the guide you suggested … But seriously how do I join the “buyers guild”?
Is there like a sekret society marijuana grow quest i must go on to be admitted membership, kill any monsters on the way type of thing?


I use it because it is collecting in a bucket by the grow room door. If we use ppm as a measure of water contamination, then there can’t be much it my condensation. It’s never been above 50, and usually is around 20.