DIY PH Down from Sulfuric Acid. (Battery Acid)

waterdawg

Well-Known Member
Hey waterdawg, how did you like the home made pH down? I'm thinking of using it to get extra Sulfur in my res. Looking for opinions
Hey Alpha I've been gone from here for a bit but drop in periodically to watch the train wrecks but dont get involved lol. Funny you should ask about the sulphuric acid as I just started using it again this run (god bud). One of the reasons was the addition of sulphur like you stated, the other was I ran out of the store stuff. Yes it works great as far as I have found. I haven't burned my hands, arms off yet lol. I find that I have to add a bit more than my other bottled stuff but I may have mixed it a tad weak. I mixed it up a year ago and forget the ratio. But yup workin great!!!!
 

AlphaPhase

Well-Known Member
I hear you brother, so many train wrecks too little time lol. That's good to know about the acid, I'm going to give it a try, it sounds perfect for what I want it for, serves more than one purpose, win win 8-) hope you are doing well man @waterdawg
 
hey carthoris im with ya on this one bro. Ive never used it before but from what i understand about ph i dont see no reason what so ever of why not to use it. I will definately give it a try. why? because if you dont try it then you will never know for sure. on the other hand ive used vinegar for adjusting my ph and everything was fine so i really dont see why car battery acid would not work or why i wouldnt give it a shot. im a pioneer, i didnt get to where im at by just doing the same old thing that the same people do over and over and over again. expand your knowledge a bit and if you make mistakes on the way well then learn from them. plus rep for the info bro
How does vinegar work? I know you can use vinegar/soap/water in a spray bottle to get rid of mites. I've never heard it used to adjust Ph???
 

brokencage

Active Member
Necro! Iv been doing this for a couple grows now GH powdered ph down has gone up so I said fuck it and gave it a try. Im sold, this works perfect. I do about a cup and a half to a gallon so i only have to add 1-2 ML at a time to adjust my 15 gal res. Thank you for a great work around. I love cheap!
@ Doc "How does vinegar work?" works awsome for about 15 mins the ph starts to rise again RAPIDLY!! Viniger dose not last. Just use the battery electrolyte.
 

bird mcbride

Well-Known Member
Dolomite lime from a lumber yard can be used as PH down also and is extremely cheap as well and a bag can last forever. Every source of sulfuric acid has seen lead and other metals at some point. The amount of contaminant would however be negligable. Plant ashes can be used to up the PH and add carbon. Any PH up or down has to be used sparingly using only the required amounts.
 

Yesdog

Well-Known Member
hah, i know i've raised threads from the dead before, but my god is this one old.....

anyways, for those of you worried about 'unclean' battery acid, just get the reagent grade stuff:

https://store.schoolspecialty.com/OA_HTML/ibeCCtpItmDspRte.jsp?minisite=10029&item=3141854

6M is about 33%, and it's reagent grade (probably just mixed from the 98%) so it's about as pure as you can get. It's a little more expensive, but still damn... $8 for 500ml of concentrated. You'll probably mix that down 1:10 and get 5L of pH down in the end for $8.
 

ttystikk

Well-Known Member
hah, i know i've raised threads from the dead before, but my god is this one old.....

anyways, for those of you worried about 'unclean' battery acid, just get the reagent grade stuff:

https://store.schoolspecialty.com/OA_HTML/ibeCCtpItmDspRte.jsp?minisite=10029&item=3141854

6M is about 33%, and it's reagent grade (probably just mixed from the 98%) so it's about as pure as you can get. It's a little more expensive, but still damn... $8 for 500ml of concentrated. You'll probably mix that down 1:10 and get 5L of pH down in the end for $8.
Seven pages of idiots who don't know their chemistry.

Wtf is pH down anyway if not an acid?! Lmao!

Stupid, ignorant, arrogant assholes. The cannabis industry is full of them.

I've used sulphuric acid straight from Autozone. Works fine. It's a hassle to mix down, is all.

Learn your chemistry and nutes cease to be a mystery. Then you'll understand just how badly the major industry suppliers have been ripping off the uneducated!
 

Yesdog

Well-Known Member
Seven pages of idiots who don't know their chemistry.

Wtf is pH down anyway if not an acid?! Lmao!

Stupid, ignorant, arrogant assholes. The cannabis industry is full of them.

I've used sulphuric acid straight from Autozone. Works fine. It's a hassle to mix down, is all.

Learn your chemistry and nutes cease to be a mystery. Then you'll understand just how badly the major industry suppliers have been ripping off the uneducated!
amen
 

ttystikk

Well-Known Member
In another thread I spoke about my trip to Colorado Springs yesterday. I bought dry nutrient salts from these fine folks;

www.Hydro-gardens.com

I paid LESS THAN A DOLLAR A POUND.

A pound is roughly what's in a standard size water bottle nutrient of the sort one sees in the hydro shop. Figure your markups from there, kids.
 

Yesdog

Well-Known Member
I would have been mixing my own nutrients already if I had the space- its unbelievable how cheap and customized you can get. And if you read around enough (especially agriculture white papers) you quickly realize how much more simple and direct dealing with nutrients is.

Found a recipe yesterday for a micro solution that doesnt contain calcium. Basically its a 3-part solution with calcium being its own part- only chelated nutrient needed is iron. In part you're getting screwed with expensive and complicated chelates just so they can sell you an A/B solution while shipping the least amount of water as possible- the thing we all have pretty easy access to.

Plus all of these 'magic' pH buffers which you'll mostly be scraping off of the bottom of your rez after it precipitates out (can't buffer forever). GH ph downs 'premium buffer'- Ammonium dihydrogen orthophosphate- basically the stuff they use in those crystal growing sets for kids. And people are worried about sulfuric acid being toxic? Phosphate buffers also have a tremendous ability to react with calcium as a precipitate, which basically acts as its own up buffer. You're leaching and locking ions in your solution just because "ph buffering" sells well.

If you read around more, you'll find that calcium and magnesium are often used for phosphate removal (by precipitation). This also raises ph! You're fighting a war that you really don't need to fight and you're probably giving yourself calmag defs. Sulfuric acid is a unique (and highly energetic) acid that is often used in combination with other acids to make them more effective. It is very stubborn as far as giving up the SO4 ion- meaning its more likely to stay an acid, and not 'reduce' itself down to a more stable state. Pretty much any white paper on hydroponics i read uses sulfuric acid or sometimes nitric acid as a down, and sometimes citric acid as a buffer.

The only danger you have with sulfuric acid is Calcium Sulfate precipitation- which is still between 20-200x more soluble than most calcium precipitates- and I think even that can be mitigated by using nitric acid first. Citric acid can also be used to chelate calcium (this is why there's citric acid in GH ph down- attempts to avoid precipitates), but it is rather weak, and works best when applied to the solution while still alkaline.

Meh, I'll just drop this sorted solubility list here if anybody is interested (at 15 C, most soluble first, units in g/100ml):

Calcium nitrate 121.2
Magnesium nitrate 69.5
Magnesium acetate 53.4
Magnesium sulfate 35.1
Calcium acetate 34.7
Magnesium citrate 20
Calcium sulfate 0.255
Calcium citrate 0.095 (25 °C)
Magnesium carbonate 0.039
Calcium phosphate 0.002
Calcium carbonate (Calcite) 6.17×10−4
Magnesium phosphate 2.588×10−4

But if you look at where the phosphates are, and read about how phosphorus cycle works in soil... it seems kinda obvious you want to avoid them as much as possible in hydroponics (at least in runaway amounts like you might end up with in a ph battle).
 
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ttystikk

Well-Known Member
I would have been mixing my own nutrients already if I had the space- its unbelievable how cheap and customized you can get. And if you read around enough (especially agriculture white papers) you quickly realize how much more simple and direct dealing with nutrients is.

Found a recipe yesterday for a micro solution that doesnt contain calcium. Basically its a 3-part solution with calcium being its own part- only chelated nutrient needed is iron. In part you're getting screwed with expensive and complicated chelates just so they can sell you an A/B solution while shipping the least amount of water as possible- the thing we all have pretty easy access to.

Plus all of these 'magic' pH buffers which you'll mostly be scraping off of the bottom of your rez after it precipitates out (can't buffer forever). GH ph downs 'premium buffer'- Ammonium dihydrogen orthophosphate- basically the stuff they use in those crystal growing sets for kids. And people are worried about sulfuric acid being toxic? Phosphate buffers also have a tremendous ability to react with calcium as a precipitate, which basically acts as its own up buffer. You're leaching and locking ions in your solution just because "ph buffering" sells well.

If you read around more, you'll find that calcium and magnesium are often used for phosphate removal (by precipitation). This also raises ph! You're fighting a war that you really don't need to fight and you're probably giving yourself calmag defs. Sulfuric acid is a unique (and highly energetic) acid that is often used in combination with other acids to make them more effective. It is very stubborn as far as giving up the SO4 ion- meaning its more likely to stay an acid, and not 'reduce' itself down to a more stable state. Pretty much any white paper on hydroponics i read uses sulfuric acid or sometimes nitric acid as a down, and sometimes citric acid as a buffer.

The only danger you have with sulfuric acid is Calcium Sulfate precipitation- which is still between 20-200x more soluble than most calcium precipitates- and I think even that can be mitigated by using nitric acid first. Citric acid can also be used to chelate calcium (this is why there's citric acid in GH ph down- attempts to avoid precipitates), but it is rather weak, and works best when applied to the solution while still alkaline.

Meh, I'll just drop this sorted solubility list here if anybody is interested (at 15 C, most soluble first, units in g/100ml):

Calcium nitrate 121.2
Magnesium nitrate 69.5
Magnesium acetate 53.4
Magnesium sulfate 35.1
Calcium acetate 34.7
Magnesium citrate 20
Calcium sulfate 0.255
Calcium citrate 0.095 (25 °C)
Magnesium carbonate 0.039
Calcium phosphate 0.002
Calcium carbonate (Calcite) 6.17×10−4
Magnesium phosphate 2.588×10−4

But if you look at where the phosphates are, and read about how phosphorus cycle works in soil... it seems kinda obvious you want to avoid them as much as possible in hydroponics (at least in runaway amounts like you might end up with in a ph battle).
Or just use premixed dry nutrients where they've done all the work for you already and it averages less than a dollar per pound?

I get convenience, storage, great nutrient balance, flexibility and that extremely low price, all in one package deal.

Www.Hydro-gardens.com
 

Yesdog

Well-Known Member
Or just use premixed dry nutrients where they've done all the work for you already and it averages less than a dollar per pound?

I get convenience, storage, great nutrient balance, flexibility and that extremely low price, all in one package deal.
Yea when I get the space I'm going with the Hydroponic Special 5-11-26, $7 for 1 lb of dry salts- should be able to make almost 100gal (total nutrient solution). Still can get cheaper, but damn its better than liquid premix

EDIT: eh, or ill just drive to colorado springs some time and stock up. They do have some pretty good prices, but I feel like I would leave with... way too much.
 

churchhaze

Well-Known Member
Found a recipe yesterday for a micro solution that doesnt contain calcium. Basically its a 3-part solution with calcium being its own part- only chelated nutrient needed is iron. In part you're getting screwed with expensive and complicated chelates just so they can sell you an A/B solution while shipping the least amount of water as possible- the thing we all have pretty easy access to.
.
I m actually using a DIY 2 part and the only chelated ingredient I used is iron DTPA. You can mix iron DTPA with calcium nitrate in the same stock solution. I use 400 concentration factor for my A+B, but realistically it's not like I can rip myself off. I dilute enough so that 10mL of A and B goes to 1 gallon of water.
 

churchhaze

Well-Known Member
Pretty much any white paper on hydroponics i read uses sulfuric acid or sometimes nitric acid as a down
The only danger you have with sulfuric acid is Calcium Sulfate precipitation
It sucks how only one brand of pH down I know of uses nitric acid, and it's relatively weak. Nitric acid is the best at keeping stuff in the water and the nitrate form of all the metals is more soluble than the phosphate/sulfate versions! NO3- 4 life.

I also use battery acid mostly because nitric acid is harder to come by and technaflora ph down is expensive/watered down, but nitric acid is really the key to hard water.
 

ttystikk

Well-Known Member
Yea when I get the space I'm going with the Hydroponic Special 5-11-26, $7 for 1 lb of dry salts- should be able to make almost 100gal (total nutrient solution). Still can get cheaper, but damn its better than liquid premix

EDIT: eh, or ill just drive to colorado springs some time and stock up. They do have some pretty good prices, but I feel like I would leave with... way too much.
The good news is that as a dry nutrient, it keeps and keeps and keeps.... :fire:
 
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