Living Organic Soil, RO water, and pH. What's the deal here?

Reverse Osmosis system is working at peak performance, pH from faucet at a near perfect 7.0 and a TDS/PPM of under 20

Have suffered deficiencies in previous grows and overwhelming consensus seems to say LED + RO water means additional Ca/Mg is a must

So I bought this stuff: https://www.planetnatural.com/product/camg/

and this stuff to adjust pH which is pro-beneficial:

After adding the CaMg+ from General Organics, the water pH plummets (NOT rises) to around 5.6 pH.

So what do I do? So much ridiculous conflicting information out there about people claiming with organics you don't need to pH. Well are those people taking into consideration that other peoples untreated tapwater can contain chloramines and ridiculously high TDS? So those of us resort to RO. And then find out "Oh our advice wasn't meant for RO"..

Would greatly appreciate some advice! Thank you in advance

Water sounds just fine to me. I don't believe it would affect your organic soil at all, as long as your soil is well amended.

Try some dolomite lime for your calmag.
It'll break down slowly and dissolve over time. Making your soil's ph more stable, with less swings. While also providing a continuous supply of calcium and magnesium.

If you can do without it, leave bottled stuff on the shelf. That's generally where it belongs imho.

Aussieaceae said:

Water sounds just fine to me. I don't believe it would affect your organic soil at all, as long as your soil is well amended.

Try some dolomite lime for your calmag.
It'll break down slowly and dissolve over time. Making your soil's ph more stable, with less swings. While also providing a continuous supply of calcium and magnesium.

If you can do without it, leave bottled stuff on the shelf. That's generally where it belongs imho.

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Thanks for the reply!

I do believe it definitely is needing some kind of Ca/Mg supplement. I developed deficiencies in flower last grow and I'm thinking it was due to simply feeding it straight RO water the entire time..

Would you pH down the water if it comes out at 7?

deimos phobos said:

Thanks for the reply!

I do believe it definitely is needing some kind of Ca/Mg supplement. I developed deficiencies in flower last grow and I'm thinking it was due to simply feeding it straight RO water the entire time..

Would you pH down the water if it comes out at 7?

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No neutral is ideal imo. 20ppm as well, there is zilch to have an effect on soil ph. There just isn't anything in the water to do it. Ph'ing your water is pointless in this regard.
Worry about what's actually in your soil. That's what's going to effect ph most of all.
Water is more of a hydroponic concern. Soil it's much different, only extremely shitty water will effect it.

If you have plants showing calmag deficiency. Try a sprinkle of dolomite lime on top your soil. Put a little mulch ontop, then water it in.
It should help.
Next time you water would be the perfect time to do so.

Happy to help. Good luck.

Edit: next time you start your mix, put some dolomite in there. Doesn't have to be a lot either. At a guess, a handful or two per 20L of soil should be fine. You can always top dress like I suggested, if you need more down the road.

Just keep adding worm castings. D-lime every so often maybe once or twice yearly. Ph won't ever be an issue if you keep the mix highly active with microbes by adding back lots of ewc. Only problem with heavy composts is you may also need to lighten up the mix with perlite and/or coco for drainage. A worm factory is a wise investment.

deimos phobos said:

So much ridiculous conflicting information out there about people claiming with organics

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This is why I started getting my soil tested, to cut the confusion. These test kits come with prepaid postage and lab fees. All you have to do is fill out the card, use the dirt scooper(provided) to fill the container(provided), and mail it in. I can justify that the cost of the test because getting back on track is worth the money. I can probably make a good guess at your problems, but it's just a guess. You are probably very high in phosphorus that is causing iron chlorosis and deficiency in micronutrients with Mn being near zero. That's how they usually go from myself and other members on here that used Soil Savvy... https://www.amazon.com/Soil-Savvy-Understand-Fertilizer-Recommendation/dp/B01GIMOG8A/ref=sr_1_1_sspa?keywords=soil+savvy&qid=1580325406&sr=8-1-spons&psc=1&smid=A2V54623UJXEW9&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyNENMSFhIMVBKUTNPJmVuY3J5cHRlZElkPUEwMzI3OTA2S1NRVkgzM0VINE1WJmVuY3J5cHRlZEFkSWQ9QTA4NDMwNjYzOFY1SThFVzY1TTlUJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

deimos phobos said:

I do believe it definitely is needing some kind of Ca/Mg supplement.

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Using this could kill your potassium and I think that it's for people using coco coir and not peat. Like I said though, a $30 test could get you out of the dark and no more guessing...

The cannabis cal/mag supplement is a holdover from the bro science days of prohibition. I highly doubt your soil is deficient in calcium or magnesium after only one run through. I’ve got potting soil that has 8 or 9 runs without adding anything concerning calcium or magnesium inputs. Almost All of the inputs in your soil mix have calcium and magnesium present. I understand you’re frustrated as I’ve been there before but before you start buying/adding bottled products test your soil and wait for the results. I have a high suspicion that there are super high levels of one of the macro nutrients, I Guess phosphorous as this is one that can cause serious issues. Get your test results and then you’re able to make an educated plan. Until then you’re most likely just compounding the problem by adding all these synthetic bottled products.

I’d just keep adding straight well water or rain water if you can collect it.Like Aussie said, little chance your water is so bad that it is causing major issues with how long you’ve been using it.Your water shouldn’t be the source of C or Mg for your plants.

Growitpondifarm said:

The cannabis cal/mag supplement is a holdover from the bro science days of prohibition. I highly doubt your soil is deficient in calcium or magnesium after only one run through. I’ve got potting soil that has 8 or 9 runs without adding anything concerning calcium or magnesium inputs. Almost All of the inputs in your soil mix have calcium and magnesium present. I understand you’re frustrated as I’ve been there before but before you start buying/adding bottled products test your soil and wait for the results. I have a high suspicion that there are super high levels of one of the macro nutrients, I Guess phosphorous as this is one that can cause serious issues. Get your test results and then you’re able to make an educated plan. Until then you’re most likely just compounding the problem by adding all these synthetic bottled products.

I’d just keep adding straight well water or rain water if you can collect it.Like Aussie said, little chance your water is so bad that it is causing major issues with how long you’ve been using it.Your water shouldn’t be the source of C or Mg for your plants.

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I think you're absolutely right about calcium and magnesium. It isn't often needed as often, or as abundantly as what they say. It's all about the right balance.

Problem I do find though, is a lot of growers use too much rich organic matter, or fertilizer. Causing an abundance of anions like sulphur and phosphorus, causing lockout / deficiency. Causing the encouragement of anerobic activity. Inevitably leading to a drop in soil ph, soil health and eventually structure.
Calcium and magnesium are essential for keeping the right balance in check and helps when locking out. It's pretty hard to overdo imoe, unless in liquid form.

Aussieaceae said:

No neutral is ideal imo. 20ppm as well, there is zilch to have an effect on soil ph. There just isn't anything in the water to do it. Ph'ing your water is pointless in this regard.
Worry about what's actually in your soil. That's what's going to effect ph most of all.
Water is more of a hydroponic concern. Soil it's much different, only extremely shitty water will effect it.

If you have plants showing calmag deficiency. Try a sprinkle of dolomite lime on top your soil. Put a little mulch ontop, then water it in.
It should help.
Next time you water would be the perfect time to do so.

Happy to help. Good luck.

Edit: next time you start your mix, put some dolomite in there. Doesn't have to be a lot either. At a guess, a handful or two per 20L of soil should be fine. You can always top dress like I suggested, if you need more down the road.

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Quick question- I’m doing a first run in soil with bio bizz light mix and their nutes.
My water from the tap is a ph of 8.2. Should I be concerned about that at all? Or just mix with their nutes and feed?

@BuddingHorticulturist

That's a good question, in all honesty, I can't realistically answer.
I've never used either bio bizz products, so haven't the faintest in regard to those.

I'd start by testing your water. 8.2 would be pretty manageable in my case, if the ec / pmm of the water wasn't too bad.
Test the ec/ppm of your water and play it by ear from there.
Containers might be a little more sensitive.
More than a few hundred ppm and I'd start to question what's in the water. Because you might get buildup of whatever it is, in your pot.

You'll just have to wait and see. Sorry I can't really give a better answer.

Would it hurt adjusting the water from 8.2 to ph6.5 - 7? I highly doubt it would.
It's far more important what the ec/pmm reading is imo. It's far more important what's actually in there.

Edit: As someone here mentioned in another thread you're in. Don't adjust ph before adding nutrient either.

Aussieaceae said:

@BuddingHorticulturist

That's a good question, in all honesty, I can't realistically answer.
I've never used either bio bizz products, so haven't the faintest in regard to those.

I'd start by testing your water. 8.2 would be pretty manageable in my case, if the ec / pmm of the water wasn't too bad.
Test the ec/ppm of your water and play it by ear from there.
Containers might be a little more sensitive.
More than a few hundred ppm and I'd start to question what's in the water. Because you might get buildup of whatever it is, in your pot.

You'll just have to wait and see. Sorry I can't really give a better answer.

Would it hurt adjusting the water from 8.2 to ph6.5 - 7? I highly doubt it would.
It's far more important what the ec/pmm reading is imo. It's far more important what's actually in there.

Edit: As someone here mentioned in another thread you're in. Don't adjust ph before adding nutrient either.

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dude, thank you so much! My ppm is sitting at like 180. Side note- I do use this same water for my veggie garden and it seems to work great. Maybe I’ll test it out, half the plants with ph neutral water and the other half with tap water to see the difference

BuddingHorticulturist said:

dude, thank you so much! My ppm is sitting at like 180. Side note- I do use this same water for my veggie garden and it seems to work great. Maybe I’ll test it out, half the plants with ph neutral water and the other half with tap water to see the difference

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Great idea man!

Mine's generally around the same, but ph is closer to neutral. Container soil it's absolutely fine for me and DTW hydro.
Water culture was a bit different and it would spike straight back to 7, not long after adjustment. Had to use way too much acid to keep it stable and hated it. RO would have been the simplest solution.
Try adjusting the ph to neutral on a bucket full of water, then let it sit overnight. See what it reads in the morning. It'll give some idea as to what's going on.
Chances are if your veggies like it, it should be fine. Only time will tell.

Not a problem, happy to help.
Good luck.

deimos phobos said:

Reverse Osmosis system is working at peak performance, pH from faucet at a near perfect 7.0 and a TDS/PPM of under 20

Have suffered deficiencies in previous grows and overwhelming consensus seems to say LED + RO water means additional Ca/Mg is a must

So I bought this stuff: https://www.planetnatural.com/product/camg/

and this stuff to adjust pH which is pro-beneficial:

Shop | Hawthorne Gardening Company

The largest and most experienced supplier of horticulture, organics, hydroponics, and lighting supplies. We are a distributor for leading brand name suppliers such as Gavita, Eye Hortilux lamps, Grodan rockwool, General Hydroponics, Botanicare, Bloombastic, Atami, Hydro Dynamics, Roots Organics...

www.hawthornegc.com

After adding the CaMg+ from General Organics, the water pH plummets (NOT rises) to around 5.6 pH.

So what do I do? So much ridiculous conflicting information out there about people claiming with organics you don't need to pH. Well are those people taking into consideration that other peoples untreated tapwater can contain chloramines and ridiculously high TDS? So those of us resort to RO. And then find out "Oh our advice wasn't meant for RO"..

Would greatly appreciate some advice! Thank you in advance

Click to expand...

Not having to ph your water only means your amendments are enough to buffer whatever you have. If you have enough powdered dolomite lime buffering constantly, you shouldnt have to worry about it. If you think your soil is not buffering the ph correctly, you can fix this by adding 1 tablespoon of powdered dolomite lime and 1 tablespoon of molasses in about 3 liters of water. This will help bind the dolomite to the surrounding area and should fix any ph issues you're having by buffering it all to 7.

If you believe your water contains any toxic chems or anything harmful, you can perform a relatively cheap (14 dollars) test you get from amazon which will let you know if there is something harmful there. Or you can take your water a treatment facility but that cost a bit more.

What is the ppm of your water straight out of the faucet? Getting that first is good information to have.


Side note. If you use lime, make sure its dolomite powder. There are a ton of different limes out there and they dont do the same things. Ive seen a lot of people put in the wrong one thinking its what they need.

deimos phobos said:

Reverse Osmosis system is working at peak performance, pH from faucet at a near perfect 7.0 and a TDS/PPM of under 20

Have suffered deficiencies in previous grows and overwhelming consensus seems to say LED + RO water means additional Ca/Mg is a must

So I bought this stuff: https://www.planetnatural.com/product/camg/

and this stuff to adjust pH which is pro-beneficial:

Shop | Hawthorne Gardening Company

The largest and most experienced supplier of horticulture, organics, hydroponics, and lighting supplies. We are a distributor for leading brand name suppliers such as Gavita, Eye Hortilux lamps, Grodan rockwool, General Hydroponics, Botanicare, Bloombastic, Atami, Hydro Dynamics, Roots Organics...

www.hawthornegc.com

After adding the CaMg+ from General Organics, the water pH plummets (NOT rises) to around 5.6 pH.

So what do I do? So much ridiculous conflicting information out there about people claiming with organics you don't need to pH. Well are those people taking into consideration that other peoples untreated tapwater can contain chloramines and ridiculously high TDS? So those of us resort to RO. And then find out "Oh our advice wasn't meant for RO"..

Would greatly appreciate some advice! Thank you in advance

Click to expand...

deimos phobos said:

Reverse Osmosis system is working at peak performance, pH from faucet at a near perfect 7.0 and a TDS/PPM of under 20

Have suffered deficiencies in previous grows and overwhelming consensus seems to say LED + RO water means additional Ca/Mg is a must

So I bought this stuff: https://www.planetnatural.com/product/camg/

and this stuff to adjust pH which is pro-beneficial:

Shop | Hawthorne Gardening Company

The largest and most experienced supplier of horticulture, organics, hydroponics, and lighting supplies. We are a distributor for leading brand name suppliers such as Gavita, Eye Hortilux lamps, Grodan rockwool, General Hydroponics, Botanicare, Bloombastic, Atami, Hydro Dynamics, Roots Organics...

www.hawthornegc.com

After adding the CaMg+ from General Organics, the water pH plummets (NOT rises) to around 5.6 pH.

So what do I do? So much ridiculous conflicting information out there about people claiming with organics you don't need to pH. Well are those people taking into consideration that other peoples untreated tapwater can contain chloramines and ridiculously high TDS? So those of us resort to RO. And then find out "Oh our advice wasn't meant for RO"..

Would greatly appreciate some advice! Thank you in advance

Click to expand...

Just strolled across this thread and I’m glad I did.
I have a closet grow 2x4x8.
3 purple Afghan Kush
Started under 96 watt t5 until 6 weeks old in living soil using ro water.
Started to get mag deficient so leaned on camg by Botanicare and things got better.
Transplanted waited three days then brought in an electric sky 300 at 50 percent strength.
within 3 daysI had one plant showing the first photo I watered with 350 ppm ca mg and the photos lower are this morning 48 hours after camg watering.

no doubt if your using ro water in living soil you’d better understand where yiur ca and mg arecoming from or you could have issues. StrongLED lights do some to quicken the onset it seems