Medium pH Correction (Soil and Coco)

XtraGood

XtraGood

Well-Known Member
Now that I've got you guys worked up about quality, maybe you'd take a look at my first grow and see if I'm wrecking things there? LINK
 
GrassBurner

GrassBurner

Well-Known Member
@DoubleAtotheRON , I worked at a machine shop and ran a water jet machine years ago. One of the first days I was learning to operate the machine, my boss brought a raw carrot over to the nozzle, turned it on, and ran the carrot through the jet as fast as he could. It cut through like a hot knife through butter. Told me my fingers dont stand a chance against 50k psi of sand and water. Stuck a big ass beef rib bone in a press once as well. I think he liked destroying things, but it was informative. Always stuck with me, nothing like seeing the power of a dangerous tool in action.
 
DoubleAtotheRON

DoubleAtotheRON

Well-Known Member
Yeah, those are cool. First time I got a good 3300 PSI pressure washer, I was standing by an old piece of wood fence, I put in the needle nozzle and wrote my name in it.. all the way through it! ... also grazed my rubber boot with it, and sliced into the tip of my toe. You could kill someone with one of those things pretty quick.
 
Kassiopeija

Kassiopeija

Well-Known Member
PadawanWarrior said:
I've been using citric acid in my water when I want to lower the pH in my organic soil.
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But it's not stable in the long run... if you for example set the pH of a waterdrum using citric acid the pH will return being alkaline after a few days.

On an unrelated sidenote - there's also pH down available based on Nitric Acid - that would be the one to prefer in veg.
 
PadawanWarrior

PadawanWarrior

Well-Known Member
Kassiopeija said:
But it's not stable in the long run... if you for example set the pH of a waterdrum using citric acid the pH will return being alkaline after a few days.

On an unrelated sidenote - there's also pH down available based on Nitric Acid - that would be the one to prefer in veg.
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Check out this Humboldt State University study. They can explain the effects that citric acid has on soil pH better than I can.
 
GrassBurner

GrassBurner

Well-Known Member
Looks like citric acid is the only one that doesn't contain any extra elements. The others might require an adjustment in nutrients when used to adjust ph. The article stated that the ph of the soil was lowered over the duration of the experiment, so I'm guessing it stayed around long enough to continue to work. They did state citric acid was the only one that was biodegradable, so from an environmental standpoint citric acid is a good choice. I guess as long as your soil isnt checked full of heavy metals, citric acid used to lower water ph isnt going to have any significant ill effects.
 
A

Apalchen

Well-Known Member
Not sure how I missed this post but love the info. Def getting one of those meters as soon as I can.

Do they make any systems that have multiple stakes that can just be left in plants and the info be sent back to a base station. Would love to see real time numbers by just pulling up an app.
 
Renfro

Renfro

Well-Known Member
Citric acid, if it was a good and stable pH buffer then I suspect companies like general hydroponics would be selling it as their pH down. It is weak sauce IMO and if it works for you great but I wouldn't go hog wild and buy a lot of it until you know it works good in your situation.
 
S

spek9

Well-Known Member
Renfro said:
Citric acid, if it was a good and stable pH buffer then I suspect companies like general hydroponics would be selling it as their pH down. It is weak sauce IMO and if it works for you great but I wouldn't go hog wild and buy a lot of it until you know it works good in your situation.
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I tried using citric acid as a pH down for a while a few years ago. I was using smaller stock tanks than I do now, but nonetheless... I found that when I used it, the pH would slowly but continuously creep back up, so I was pH-ing once at time of stock tank mix, then again when I went to feed.

Then I was finding that my medium (Promix HP at the time) was acting strange after a while, and had to start adding something to up the pH to get the plants to behave properly. I didn't test the medium or runoff or anything like that, but I stopped using the stuff as I was finding it too unpredictable and unreliable over the long term.

Maybe it works for the odd one-off, but for me, I found it problematic as a long-term pH down solution.
 
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PadawanWarrior

PadawanWarrior

Well-Known Member
spek9 said:
I tried using citric acid as a pH down for a while a few years ago. I was using smaller stock tanks then than I do now, but nonetheless... I found that when I used it, the pH would slowly but continuously creep back up, so I was pH-ing once at time of stock tank mix, then again when I went to feed.

Then I was finding that my medium (Promix HP at the time) was acting strange after a while, and had to start adding something to up the pH to get the plants to behave properly. I didn't test the medium or runoff or anything like that, but I stopped using the stuff as I was finding it too unpredictable and unreliable over the long term.

Maybe it works for the odd one-off, but for me, I found it problematic as a long-term pH down solution.
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I dont use it to adjust my water really. I know it's a short fix for that. I use it to lower my soil pH when I've added too much Ca. I normally just give my plants plain water that's at around 7.4, but once in awhile they'll get Neptune's Harvest or something and the water pH will be lower. I'm learning the no-till thing.
 
Renfro

Renfro

Well-Known Member
spek9 said:
I tried using citric acid as a pH down for a while a few years ago. I was using smaller stock tanks then than I do now, but nonetheless... I found that when I used it, the pH would slowly but continuously creep back up, so I was pH-ing once at time of stock tank mix, then again when I went to feed.

Then I was finding that my medium (Promix HP at the time) was acting strange after a while, and had to start adding something to up the pH to get the plants to behave properly. I didn't test the medium or runoff or anything like that, but I stopped using the stuff as I was finding it too unpredictable and unreliable over the long term.

Maybe it works for the odd one-off, but for me, I found it problematic as a long-term pH down solution.
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Thanks for sharing your experience. I personally haven't tried the stuff. Did notice that my girl has a few bottles of the powder that she has for making bath bombs. Don't see a need to try it though as I have the good stuff.
 
C

ComfortCreator

Well-Known Member
I have been using the Apera soil meter for the last few waterings and have found it very easy to use. It definitely works and I have been trying out lowering my ph from supersoil of 7.2 with waterings at 6.0ph. So far they have responded well, but Im in late flower so its hard to discern exactly.

I can measure the rootball soon after watering at 6.5ph, then over time it goes back up to 7.2.
 
Renfro

Renfro

Well-Known Member
ComfortCreator said:
So far they have responded well, but Im in late flower so its hard to discern exactly.
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Agreed, it is a lot easier to see the results in veg and stretch.
ComfortCreator said:
I can measure the rootball soon after watering at 6.5ph, then over time it goes back up to 7.2.
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The buffers in the soil and fighting you. I have to fight it constantly, so first I use hard corrections, so in your case I might water at say 5.0 for a feed, then maybe 5.5, then 6.0 and have to hold the 6.0 for the rest of flower, maybe even another hard correction.

My Promix HP that I am using now likes to be too low and I have to feed around 7.2 - 7.3 for the plants to be happy looking. A few feeds at 8.0 had to happen first. It's a constant battle and knowing this means you should fix the soil before use next time by adding buffers to the soil itself or buying different soil.
 
C

ComfortCreator

Well-Known Member
Renfro said:
Agreed, it is a lot easier to see the results in veg and stretch.

The buffers in the soil and fighting you. I have to fight it constantly, so first I use hard corrections, so in your case I might water at say 5.0 for a feed, then maybe 5.5, then 6.0 and have to hold the 6.0 for the rest of flower, maybe even another hard correction.

My Promix HP that I am using now likes to be too low and I have to feed around 7.2 - 7.3 for the plants to be happy looking. A few feeds at 8.0 had to happen first. It's a constant battle and knowing this means you should fix the soil before use next time by adding buffers to the soil itself or buying different soil.
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Thanks Renfro I was wondering if there is a way to deal with it. Since I am so far along I didnt want to try running ph water below 6 through them but can already see what you mean.

I will remeasure my cooking soil, I think it was 6.5. If so that means as the nutes are used up the ph moves up above 7?. I know I can add dolomite lime to increase ph, which is what is in there. If I need to lower the ph would I add more peat?
 
TerrapinBlazin

TerrapinBlazin

Well-Known Member
Those ph pens are sweet. I didn’t know they existed. I’ve got one of the glass bulb ones that I’ve never used and an old fashioned test kit for my feeding. That’s a big investment though. This seems to be the cheapest one and it’s still not cheap.

Amazon.com : Bluelab PENSOILPH pH Pen for Soil, Coco, Rockwool and Solution, Easy Calibration : Soil Testers : Garden & Outdoor

Amazon.com : Bluelab PENSOILPH pH Pen for Soil, Coco, Rockwool and Solution, Easy Calibration : Soil Testers : Garden & Outdoor
www.amazon.com
 
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