Safest food grade diy ph down

dstroy

Well-Known Member
Many plants tolerate chloride well. Mangrove is one. Cannabis isn't one. 100ppm Cl- will lock out nitrate and other monovalents. It is like feeding a starving person Metamucil ... which strikes me as wilfully cruel. ~shrug~

Sulfuric acid is not a carcinogen. Sulfate is a necessary human nutrient.

So I challenge both your arguments at the root level of the facts employed to make them.
Ok, sulfuric acid causes cancer.

It's an IARC group one classification

https://www.osha.gov/dts/chemicalsampling/data/CH_268700.html

Nitric and phosphoric are not known to cause cancer. Only the workers that inhaled sulfuric acid got cancer. All inorganic acids are dangerous.

Just because our bodies need sulfur, doesn't mean that all of the different physical forms of sulfur are compatible with our physiology. (Like sulfuric acid, or sulfur dioxide)

Chloride is necessary for the chemical reaction that causes stomata to open and close. It's found in all plant tissue.
 

dstroy

Well-Known Member
Maybe you live by the water, where there is sufficient chlorine in the air to not cause deficiency. One observation by one uncontrolled experiment does not constitute concrete evidence to the contrary of the mountain of scientific data collected on essential plant nutrients funded by billions of dollars of big ag that concluded that they increase yields when fertilizing with potassium chloride in the Midwest.
 

cannabineer

Ursus marijanus
Ok, sulfuric acid causes cancer.

It's an IARC group one classification

https://www.osha.gov/dts/chemicalsampling/data/CH_268700.html

Nitric and phosphoric are not known to cause cancer. Only the workers that inhaled sulfuric acid got cancer. All inorganic acids are dangerous.

Just because our bodies need sulfur, doesn't mean that all of the different physical forms of sulfur are compatible with our physiology. (Like sulfuric acid, or sulfur dioxide)

Chloride is necessary for the chemical reaction that causes stomata to open and close. It's found in all plant tissue.
It only causes cancer as a "strong inorganic aerosol" i.e. acid smoke.

Take simplest precautions to avoid inhaling that and the cancer risk goes away.

I would choose sulfuric as a pH-down without reservation. I use phosphoric now (because i have it at hand) and in my old NFT grow I chased the pH with reagent nitric.

I would avoid hydrochloric however (with all respect to @GreatwhiteNorth, one of RIU's true gentlemen) for a coupla reasons. Not least among these is that HCl fumes are very damaging to equipment made entirely or partly of metal.
 

cannabineer

Ursus marijanus
Maybe you live by the water, where there is sufficient chloride in the air to not cause deficiency. One observation by one uncontrolled experiment does not constitute concrete evidence to the contrary of the mountain of scientific data collected on essential plant nutrients funded by billions of dollars of big ag that concluded that they increase yields when fertilizing with potassium chloride in the Midwest.
Big ag generally is concerned with other genera e.g. Triticum and Prunus. Chloride need or toleration varies among the lot of them.

In Europe the cheapest form of garden K is kainite, mineral potasium chloride. There is a list of plants (asparagus among them iirc) that carried kainite toxicity warnings. So for most plants, kainite is K yes and Cl ~we'll tolerate it~, for a net gain.

Tell me, how did KCl fare against, oh, K2SO4? They did that control, no? That would separate the effects of the two ions in kainite.
 

dstroy

Well-Known Member
Big ag generally is concerned with other genera e.g. Triticum and Prunus. Chloride need or toleration varies among the lot of them.

In Europe the cheapest form of garden K is kainite, mineral potasium chloride. There is a list of plants (asparagus among them iirc) that carried kainite toxicity warnings. So for most plants, kainite is K yes and Cl ~we'll tolerate it~, for a net gain.

Tell me, how did KCl fare against, oh, K2SO4? They did that control, no? That would separate the effects of the two ions in kainite.
You know, this argument isn't really worth it. I don't know if they had control fields, and I don't care to research it.

Sulfuric acid can cause cancer, the other two acids aren't known to. I don't see the point in arguing about this either, it's not really apples and oranges if one can cause cancer (at least to me). I can buy any of them cheaply enough, my ph down actually is phosphoric, and nitric acid. Already dilute, ready for use.

According to all of the things that I've read, chloride is an essential plant nutrient in trace amounts. ALL plants, not just certain plants, all tested plants that I've read about.

Kainite isn't just potassium chloride.
 

cannabineer

Ursus marijanus
You know, this argument isn't really worth it. I don't know if they had control fields, and I don't care to research it.

Sulfuric acid can cause cancer, the other two acids aren't known to. I don't see the point in arguing about this either, it's not really apples and oranges if one can cause cancer (at least to me). I can buy any of them cheaply enough, my ph down actually is phosphoric, and nitric acid. Already dilute, ready for use.

According to all of the things that I've read, chloride is an essential plant nutrient in trace amounts. ALL plants, not just certain plants, all tested plants that I've read about.

Kainite isn't just potassium chloride.
You're right about the kainite. I got it mixed up with mineral KCl.

As for the other argument, I maintain that H2SO4 is cheap, non-toxic and safe if used by adults.

I am certain that some chloride is necessary. But i controlled it to <1ppm, and the plants grew very well.

So it becomes a subjective response to a variable supply of objective fact. In my opinion, of course.

~edit~ mineral KCl is sylvine
 
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churchhaze

Well-Known Member
There are so many better choice salts than KCl to provide K. KNO3 (~39%, 47% K2O equivalent), KH2PO4 (28%, 34% K2O equivalent) are my sources... Of course there's also KOH for pH up which is ~70% K. (84% K2O equivalent)

People here make the same observations about silicates. "I added potassium silicate and the plants were noticeably better therefore cannabis must want silica". But K2SiO3 is ~51% K (61.2% K2O equivalent)

At least cannabis does need some Cl.. It doesn't need any Si...
 

dstroy

Well-Known Member
There are so many better choice salts than KCl to provide K. KNO3 (~39%, 47% K2O equivalent), KH2PO4 (28%, 34% K2O equivalent) are my sources... Of course there's also KOH for pH up which is ~70% K. (84% K2O equivalent)

People here make the same observations about silicates. "I added potassium silicate and the plants were noticeably better therefore cannabis must want silica". But K2SiO3 is ~51% K (61.2% K2O equivalent)

At least cannabis does need some Cl.. It doesn't need any Si...
I mean, it looks like there are a ton of plants that benefit from Si. Just sayin.

https://scholar.google.com/scholar?q=silica+plant+nutrient+&btnG=&hl=en&as_sdt=0,40&as_vis=1

Just because it isn't specifically required doesn't mean that it doesn't help.
 

applepoop1984

Well-Known Member
All mineral acids are dangerous in careless or untrained hands. I see very little difference in the Big Three: phoaphoric, nitric, sulfuric. (I discount hydrochloric because the chloride ion is useless to Cannabis and only serves to lock useful ions out.)

I find sulfuric acid to be a good way to regulate pH, and it is nearly neutral ... not in a Brønsted sense but in terms of shifting the usual nutrient ion concentrations. Battery acid is cheap, clean and effective.

Phosphoric acid has all the dangers of sulfuric: it is corrosive, non-volatile and exothermic upon dilution.

So it is my opinion that becoming parochial about pH-down choice is argument for its own sake.

This is all jmo, but that opinion has been shaped by my spending a lifetime in the synthetic-chemist shenanigan. Fwiw.
That's not entirely true the reason sulfuric is more dangerous than phosphoric is because sulfuric causes chemical as well as thermal Burns is a carcinogen and is about 6 times as strong as phosphoric acid you could make the argument that it is 6 times as dangerous based on the pH alone
 

cannabineer

Ursus marijanus
That's not entirely true the reason sulfuric is more dangerous than phosphoric is because sulfuric causes chemical as well as thermal Burns is a carcinogen and is about 6 times as strong as phosphoric acid you could make the argument that it is 6 times as dangerous based on the pH alone
No.

Phosphoric acid produces chemical burns like a champ.

The carcinogenicity is under circumstances no remotely competent home chemist will ever set up.

As for 6 time as strong - by what measure? The concept of pH loses meaning once the acid becomes highly concentrated, which is how phosphoric and sulfuric acids are supplied.

So no, you cannot make the argument without doing injury to some of the basic concepts. What makes me wonder is, why even try unless championing a personal bias? I have seen no argument against sulfuric in these pages that does not reduce to preference made policy.
 

applepoop1984

Well-Known Member
No.

Phosphoric acid produces chemical burns like a champ.

The carcinogenicity is under circumstances no remotely competent home chemist will ever set up.

As for 6 time as strong - by what measure? The concept of pH loses meaning once the acid becomes highly concentrated, which is how phosphoric and sulfuric acids are supplied.

So no, you cannot make the argument without doing injury to some of the basic concepts. What makes me wonder is, why even try unless championing a personal bias? I have seen no argument against sulfuric in these pages that does not reduce to preference made policy.
Never said phosphoric acid doesn't produce chemical burns and I didn't do the math but it's about four to six times as strong as phosphoric I'll get back to you when I do the math. Furthermore this write-up isn't for a competent home chemist it's for a beginner grower once a safer alternative to battery acid. No bias at all just looking for a safer method. And yes sulfuric is a listed carcinogen and to completely discredit that his foolhardy at best. Just look through this thread poster who works with every type of acid known to man said he would use phosphoric over sulfuric any day of the week but prefers citric
 
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cannabineer

Ursus marijanus
Never said phosphoric acid doesn't produce chemical burns and I didn't do the math but it's about four to six times as strong as phosphoric I'll get back to you when I do the math. Furthermore this write-up isn't for a competent home chemist it's for a beginner grower once a safer alternative to battery acid. No bias at all just looking for a safer method. And yes sulfuric is a listed carcinogen and to completely discredit that his foolhardy at best. Just look through this thread poster who works with every type of acid known to man said he would use phosphoric over sulfuric any day of the week but prefers citric
That is why I have not completely discredited it. Your reply insinuates that i did.

However to beat the cancer drum when sulfuric acid generally is not carcinogenic ... constitutes intellectual dishonesty. I'm here to oppose that sort of bias dressed up as reason.

Beginner growers have no business undertaking diy hydro nutrient compounding unless they have a degree or equivalent experience in a relevant field. So I disagree that this discussion is pitched at the beginners. I legitimately presume some education, credentialed or not.

I will not use citric acid. It has the same basic weakness as acetic: it is a carbon source for bacteria. That is a source of error (bacteria will play absolute hob with things like pH management, been there done that) that i won't accept.

I'd hoped citric would be a good solution. But i do not want to feed opportunistic bugs alongside the plants. Potential cost exceeds benefit, especially as I am familiar with the Big Three mineral acids discussed above.
 

indianajones

Well-Known Member
No adding co2 deprives the roots of oxygen, you want co2 in your air not your water
noob, there's always co2 in your water, it forms carbonic acid. it's called
the carbon dioxide- carbonic acid equilibrium. the "chemistry" in here is
making my head hurt.

the safest food grade pH down would be citric acid. commonly available
at grocery stores, you know, because it's food grade.
 

applepoop1984

Well-Known Member
noob, there's always co2 in your water, it forms carbonic acid. it's called
the carbon dioxide- carbonic acid equilibrium. the "chemistry" in here is
making my head hurt.

the safest food grade pH down would be citric acid. commonly available
at grocery stores, you know, because it's food grade.
mission accomplished
 

cannabineer

Ursus marijanus
The safest type of knife is a cheese spreading knife. Just saying.

http://www.dhmo.org/truth/Dihydrogen-Monoxide.html
Precisely. Safety must be multiplied by effectiveness to arrive at a more useful measure of the material's suitability for the task. Too many effective household products have been replaced by somewhat safer, much less capable replacements. I don't think of that as progress.
 

applepoop1984

Well-Known Member
Precisely. Safety must be multiplied by effectiveness to arrive at a more useful measure of the material's suitability for the task. Too many effective household products have been replaced by somewhat safer, much less capable replacements. I don't think of that as progress.
I don't think a new grow are using sulfuric acid progress phosphoric is just as good safer is not a carcinogen and is sold in food grade quality you have no argument
 

applepoop1984

Well-Known Member
There's really nothing wrong with using phosphoric acid as long as your P isn't already through the roof. There's also nothing wrong with using sulfuric acid or nitric acid. They're all the correct tools for the job. There is something wrong with using citric acid or vinegar... (or Hydrochloric acid)
I disagree I'd say phosphoric acid is the best choice and citric acid as well for new grower probably not a good idea to be messing around with sulfuric acid
 
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