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Hydrosalts and Organic Soil - Bad Practice or Perpetuated Rumor?

canabinerd

New Member
So I got into a discussion the other day about pH and using commercially available pH up and pH down solutions. And much to my surprise, have had several people tell me that using them is not good for organic soils. Now I'm not trying to ruffle feathers or start a fight here, although, I have been called all sorts of names by the people telling me this when I ask them the obvious question......why? But, I have not yet received any sort of reasonable explanation as of yet. As a matter of fact, the vast majority of the explanations I've been given don't even pass the sniff test. I am talking online with a few people about it and if that bears fruit, I'll let you know. And if all else fails, I know a botany professor that I may ask, if I can figure out how to do it without giving away my hobbies.

I do want to have an intelligent discussion about this and get to the bottom of the question not only for my own piece of mind, but so we all have information that is true. And at this point, I feel that I really cannot say one way or another whether this information is true or not with absolute certainty.

I would like to encourage people to contribute only facts to this conversation, as I have heard most of the "but this author said this and my cousin said that" at this point. Unless that author is really an authority and presented a mechanism for what's happening, it's really just more rumor. Be warned, I will fact check you.

P.S.: For all of you that may be tempted to turn this into a name calling contest, I will ignore you. I went to college AFTER I did 6 years as an enlisted man and I bet few of you would call me names to my face and fewer would be conscious after they did. If you want to have a name calling contest, open another thread in the off topic forum, I've got lots of them. This is for science.
 

canabinerd

New Member
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

So this is the final word I got from FoxFarm and the closest thing to an answer so far:

"Thank you for your reply, I will explain what I understand about this issue, but I am not a biochemist. When you add a pH buffering agent to a finished nutrient solution, a rapid swing in pH is actually what kills the biota. If you add the adjustment solution very slowly, it cannot create this dramatic swing, thereby preserving your beneficials. When you add your whole amount of pH up or down to your nutrient solution all at once, the cloud that moves through the solution drastically affects the nutrients and beneficials that it comes in contact with killing them by corrosion. If you add the buffering agent very slowly, the pH swing is more gradual and will not kill the beneficial microbes. Phosphoric acid and potassium hydroxide are both caustic, but when diluted, they are not able to oxidize your solution. I hope this helps. Please let me know if you have any more questions".



Thank you for your correspondence, and thank you for growing with FoxFarm.


I think I'll contact General Hydroponics next, obviously they're biased, but they might have a chemist or biochemist on staff. I'm really not happy with the above answer. While at first glance it sounds reasonable, once you think about it for two seconds it really doesn't answer my question. Are a lot of people culturing bacteria and fungi in their nutrient solution prior to watering with it? If you are, this is of prime importance to you. If not, it doesn't mean anything, because if you are adjusting your pH prior to putting it in the soil and matching the pH to what your soil is buffered at. That means you are actually providing a better environment for your soil biota and creating less salt build-up.
 

canabinerd

New Member
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

Anyone have any input, know of someone who would know, etc.? I mean I buy the pH swing thing, that could certainly be bad. And I guess that means it might be best use a soil probe so you know the pH prior to putting any new water in regardless of what kind of nutrients your using. That's not a problem unique to hydroponic pH up and down though. You could do that just as easily with any pH buffering agent or water that was out of range for that matter.
 

canabinerd

New Member
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

So, I'm gonna keep bumping this for a while, should get a response from GH soon. I have reached out to a couple of our more prestigious members in private so as not to call anyone out publicly. And they haven't had anything to contribute as of yet. So pending any further correspondence, I am expecting to chalk this up to observations turning into accepted (but not exactly true) knowledge before being analyzed and understood.

On a side note, I know some folks absolutely do not recommend using these products with their systems. And I would recommend you listen to them when using their methods.
 

canabinerd

New Member
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

Well other than learning some stuff that I didn't know, no luck yet. Even searched some scholarly articles which at least at this point contradict a lot of the claims I've heard but don't really support any. I am checking into a claim about total alkalinity, which at the surface has some merit to it; although, not to nearly the extent that was claimed. Total alkalinity is basically just a measure of all the alkaline ions in solution, or ions able to absorb protons. So really it's just a different way of looking at the buffering capacity of the solution. Sounds really official, but doesn't really change much about the conversation. Basically, carbonate and bicarbonate are the major contributors as they are weak bases and have a high capacity to soak up protons (good buffers). That's why we put dolomite [(CaMg)(CO3)2] and other mineral salts into our soil.

Now I must admit, If you are somebody that is using a lot of powdered rock, or other mineral salts in your soil mix. Even though everything I read says hydroxide is only a minor contributor. I definitely could not argue that you could possibly have problems if you used a large amount of pH up over a long period of time. If that occurred, it should be somewhat easily identifiable and correctable through flushing. If that did occur, you would have a relatively constant high pH (>7) that was resistant to adjustment with acid.
 

canabinerd

New Member
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

Allright, I think I finally have an answer I am happy with after speaking to GH, and I think some of the people who have been aggravating me will be happy with it too. So here's what they said....

Hello,



This is a bone of contention that is somewhat of a moot point. I say this because if you are growing in organic soil that has healthy colonies of beneficial bacteria, the pH of your nutrient solution is not relevant unless it is either very acidic or very alkaline. pH is regulated in the root zone by the bacteria and the plants own root exudates. If your nutrient solution has a pH between 5 and 7 then it is fine. Unlike Hydroponic cultivation which the nutrients are only available within a certain pH range, soil grown plants are able to take up the nutrients as needed and in a wider pH range.

But, to answer your question directly, no, pH up and down when used in proper amounts will not damage the micro biology.
 

canabinerd

New Member
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

So I think in conclusion it is safe to say that it is not necessary to pH balance your nutrient solution if you are growing in a good organic soil, and have a water source that you can trust to stay within a range of 5.0 to 7.0. However, if your water source is like mine and occasionally spikes over 8 due to disinfectant tablets the construction guys use, you would be well advised to check and adjust your pH if it is outside that range.

So I think I'm pretty well done with this thread for now, I may still bump it for a few days just to give people a chance to contribute if they know something pertinent that has not been presented here.

But for now,.......myth busted.
 

tokersmokeg

On Vacation
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

thanks man seems like you where on a quest for knowledge!!i appreciate your patience with my rantings and occasional name calling
 

tokersmokeg

On Vacation
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

it would be nice to say that i was right to a point but i can concede and say that you should know that source waters ph.also this might be different with chemical nutes. in my opinion if a grower continually feeds chemical nutes to the plant a ph shift can occur.Also nature finds a way to thrive in even even the least hospitable enviroment.I have thrown seeds out the back door and had plants grow to maturity.So i try not to over complicate things it can drive one crazy. I use Botanicare pure blend pro bloom for 6 weeks then use monster bloom a chemical fert at the end till a flush.I Find this to work and on a good budget.. happy growing
 

canabinerd

New Member
Re: "Hydrosalts" and Organic Soil, Bad Practice or Perpetuated Rumor?

Well, I think we were all right to a point. Hell, I learned quite a few things during the course of researching this that will probably change how I grow in the future. I can tell you I will probably be adjusting my pH less rather than more. I think the main point of this evolution is to remember that we are all learning, otherwise we wouldn't be here.
 

MKrop420

New Member
As stated by some of the above, i am also not an expert. But from what i have read

Ph up(hydroxyl ion (OH-) + PH down(Hydrogen ion (H+)=H20
with the only extra byproducts of the reaction being several ions of Phosphorus and Potassium...

So my question would be, since we add those elements for nutrients anyway, how could they be damaging any important active beneficials? Wouldn't these beneficials not be able to survive anywhere near a nutrient balanced solution?:hmmmm:
 

canabinerd

New Member
Well, that's part of the reason I went ahead and researched this, because the things people were saying just didn't make any sense. When I first started researching this, I assumed that the pH up and down I was using was a dilute phosphoric acid and dilute sodium hydroxide. And anybody who's ever taken basic chemistry knows that those substances completely ionize in water, so you get basically a very small amount of free phosphate (which is a major component of all of our fertilizer's) or a little bit of sodium, which also is not going to hurt anything at the concentrations we're talking about.

Now it turns out that most commercial pH up and down solutions are actually pre-mixed buffer solutions that also have some other weak acids and bases mixed in, but again in very small concentrations and substances which are quite non-toxic to plants or bacteria. The only proviso is, I can't dismiss that you could possibly have problems after prolonged and heavy use of pH up, but I don't know about anybody else, but I hardly ever use pH up. My tapwater is always 7.0 or above, and that is true of most city water due to the addition of hydroxides for disinfection.
 

JJ Bones

Nug of the Month: Feb 2013
Nice thread, I enjoy when people begin asking more thorough questions such as this because it contributes to everyone's advancement in their education.

I just now found this thread otherwise I would have enjoyed chiming in earlier.

I've never heard someone mention pH up or down would cause an issue to organic soil. It doesn't make much sense to me really, the only thing that hurts the biology is hydrogen peroxide or TOO much fertilizer, usually phosphorous. That causes the fungi to go dormant, typically.

Good question, good find, good share. Thanks ;)
 

canabinerd

New Member
I've never heard fungi were especially sensitive to phosphate JJ, I'll have to check into that. I think you would have to use quite a bit of pH down before that would be an issue though. There are a lot of phosphates in organic soils to begin with compared to what I would think would be a very small amount of phosphate in pH down. Phosphoric acid is a tri-protic acid so the amount of phosphate would be really small in relation to it's ability to move the pH down.
 

Graytail

Plant of the Year: 2014 - Plant of the Month: Dec 2014 - Nug of the Month: Feb 2015, Mar & Aug 2016, Dec 2017, Aug 2018, Jan 2019 - Nug of the Year: 2017 - Photo of the Month: June 2018
I believe it's potassium that's the problem, not phosphorous. :3:
 
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