DIY PH Down from Sulfuric Acid. (Battery Acid)

Yesdog

Well-Known Member
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.
Did you do the entire micro mix from scratch? Was really interested in trying to do that one micro recipe, but I'd need to mix up like 8 different stock solutions and i just really dont have the space to store that kinda stuff safely (or basically at all). I see why they kept the calcium separate in that recipe now- they were using CaSO4 as the calcium source, which would probably just fall out of the micro mixture (bot not actually precipitate due to a double displacement). Calcium nitrate definitely seems more stable.

I finally found a place in denver where I can get all sorts of reagents, the shipping is reasonable too (UPS hazardous material shipping gets expensive fast). Probably going to get some nitric acid- using tap water here (not that hard tho) so im fighting carbonates/phosphates pretty constantly.

Also had some pretty hard fallout 2 rez changes ago, been trying everything to get rid of it, but have this nice layer of precipitates that just wont go away. I've been tracking how much GH ph down ive been adding and no good could come of it.



I'll have to find the corresponding CO2 graph, but you can see CO2 gassing off trends that match the ph rise- so guessing the carbonates are partially responsible, but i've added so much phosphates at this point to counteract it there has to be a good portion of that precipitate too.

Either way, time for a strong acid.
 

ttystikk

Well-Known Member
@Yesdog oh hell no I didn't build my own micros from scratch! 5-11-26 'plus micros' Hydroponic Special, babee! That, calcium nitrate, some epsom salt and a dash of MKP for bloom and voila! A complete regimen! I even got some potassium sulfate to play with in an effort to increase available sulfur and thus terpene expression.
 

Yesdog

Well-Known Member
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.
Yeah, I asked for technaflora down at the hydro store- they have a bunch of their line, but not the ph stuff cause they said "its all the same stuff anyways" :roll:.

The good news is that as a dry nutrient, it keeps and keeps and keeps.... :fire:
true!
 

Yesdog

Well-Known Member
@Yesdog oh hell no I didn't build my own micros from scratch! 5-11-26 'plus micros' Hydroponic Special, babee! That, calcium nitrate, some epsom salt and a dash of MKP for bloom and voila! A complete regimen! I even got some potassium sulfate to play with in an effort to increase available sulfur and thus terpene expression.
ah woops, that was to @churchhaze. Just asking out of curiosity at this point. But, pretty sure I'll be hopping on the hydro special bandwagon soon!

@Yesdog oh hell no I didn't build my own micros from scratch! 5-11-26 'plus micros' Hydroponic Special, babee! That, calcium nitrate, some epsom salt and a dash of MKP for bloom and voila! A complete regimen! I even got some potassium sulfate to play with in an effort to increase available sulfur and thus terpene expression.
Heh, and if i continue to have to add as much acid as i have been but switch to sulfuric, i might just get that sulfur boost too ;)
 
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THE KONASSURE

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!

You Tt

Do you find sulphuric acid helps get more smell and taste in bloom ? I`ve been using phosphoric based ph down sometimes some nitric in the mix...... but our tap water is full of cal so I`ve been thinking about phosphoric/cal build ups and lock outs and such

Wondering if I`d be better off swapping to a sulphur based ph down ?

It`s coco there 200L butt I refill and ph it each week, bar whatever the waterboy needs to use to top up the veg...

Should add I normally add potassium silicate 1st then ph down the water comes in between 7/8 but that`s city tap so leaf alone it`ll go up

Cheers in advance bud.
 

Yesdog

Well-Known Member
You're supposed to add potassium silicate first, it dissolves and stabilizes the best at a high ph. Technically even if its added to a solution below a pH of 10 it's at risk of falling out with Calcium. It also forms a colloidal gel suspension, so its kinda hard to tell when it does fall out.

All silicate solutions are alkaline, the pH of commercial silicate solutions ranges from approximately 10 to 13. The pH is a function of ratio and concentration and decreases with increasing silica content. The stability of a sodium silicate solution depends to a large extent on pH. All sodium silicate solutions will polymerize to form a silica gel when the pH value is reduced below 10.

Time-delayed gelation (unstable sols) can occur in pH ranges of 8-10 and 2-5. Gel formation is generally very rapid in the intermediate range ( 5-8 ). Colloidal silica sols can be prepared from sodium silicates through ion exchange, dialysis and other means.
(was about sodium and potassium silicate, says the properties are about the same, but they burn different colors)

Heard a bunch of opinions one way or the other about when to add it. The dude from scienceinhydroponics says most of it is wasted if you add it all at once and recommends just adding a little every day or so. :confused: All i know for sure is its very alkaline, the precipitate is clear, and its an alkaline buffer. So if you're already having issues with carbonates "bouncing" the ph back up, it probably won't help.

The gel is really weird, i got some on my hand before. It's very slick, clear, and really hard to wash off.

EDIT: the gel is also supposed to be great at clogging pumps
 

THE KONASSURE

Well-Known Member
You're supposed to add potassium silicate first, it dissolves and stabilizes the best at a high ph. Technically even if its added to a solution below a pH of 10 it's at risk of falling out with Calcium. It also forms a colloidal gel suspension, so its kinda hard to tell when it does fall out.


(was about sodium and potassium silicate, says the properties are about the same, but they burn different colors)

Heard a bunch of opinions one way or the other about when to add it. The dude from scienceinhydroponics says most of it is wasted if you add it all at once and recommends just adding a little every day or so. :confused: All i know for sure is its very alkaline, the precipitate is clear, and its an alkaline buffer. So if you're already having issues with carbonates "bouncing" the ph back up, it probably won't help.

The gel is really weird, i got some on my hand before. It's very slick, clear, and really hard to wash off.

EDIT: the gel is also supposed to be great at clogging pumps

Yeah I`ve seen that gel happens if you`ve used anything for ph down and then use it for silica

I normally buy the 33% potsill but I`ve found the 8% is easier to work with, about the same price too just a way bigger bottle

If the stronger stuff was cheaper I`d use that and just pre mix it with some water

50 to 200mm seems to do ok in 1l to 5L of water then chuck that into my water butt

then I ph down once I`ve filled up the butt

Sometimes I`ve used silica as a ph up, seems to work but its better to mix it with a bit of plain water before chucking it in your res or water butt
 

Yesdog

Well-Known Member
Yeah I`ve seen that gel happens if you`ve used anything for ph down and then use it for silica

I normally buy the 33% potsill but I`ve found the 8% is easier to work with, about the same price too just a way bigger bottle

If the stronger stuff was cheaper I`d use that and just pre mix it with some water

50 to 200mm seems to do ok in 1l to 5L of water then chuck that into my water butt

then I ph down once I`ve filled up the butt

Sometimes I`ve used silica as a ph up, seems to work but its better to mix it with a bit of plain water before chucking it in your res or water butt
Yea, its probably a better buffer (better ph up and just more active) if its dissolved first. Lower pH (and the solutions being hypertonic- lots of salts) might just make it drop out immediately if you add it to an already mixed rez. But i think when mixed with plain (and higher ph) water its probably forced to stay in more of a colloidal suspension- vs where its all in one area and can clump up quick if it wants to. So it may still drop out eventually, but before then it'll keep acting like a buffer and releasing some Si ions here and there.
 

ttystikk

Well-Known Member
Hmm, yea I've been using it mine.... maybe I'll just keep it out of the rez and just use it in the foliar.
The vendor told me that if I wanted to apply silica to the roots, I should run it by itself for a day or two, then dump and run nutes, but keep them entirely separate. If the silica is pushed down in pH, it turns to gel and won't be absorbed.
 

Yesdog

Well-Known Member
The vendor told me that if I wanted to apply silica to the roots, I should run it by itself for a day or two, then dump and run nutes, but keep them entirely separate. If the silica is pushed down in pH, it turns to gel and won't be absorbed.
Makes sense... maybe I'll just do a silica flush between rez changes. I've been doing a 24hr flush anyways, might as well run something in there- plus its good to keep something dissolved in the water during a flush- hypotonic water with no nutes can be hard on the plant (hence the fancy flushing solutions before harvest). The silicon probably works good as a 'filler'.
 

THE KONASSURE

Well-Known Member
The vendor told me that if I wanted to apply silica to the roots, I should run it by itself for a day or two, then dump and run nutes, but keep them entirely separate. If the silica is pushed down in pH, it turns to gel and won't be absorbed.
A lot of hydro foods seem to have silica added, just in coco I can`t see many places plants can get silica from so I add it

also sounds silly maybe but I find putting in a load of silica 1st means I`m using more ph down to get to ph5 or so that seems to make it not rise as much, if I go like 4.8 to 5.2, then a week later I find it at 6 to 6.5, I can adjust with what I mix up when making that water into feed from there

but if I came into ph8+ with foam on top of it then I`d just chuck the whole butt
 

Yesdog

Well-Known Member
A lot of hydro foods seem to have silica added, just in coco I can`t see many places plants can get silica from so I add it

also sounds silly maybe but I find putting in a load of silica 1st means I`m using more ph down to get to ph5 or so that seems to make it not rise as much, if I go like 4.8 to 5.2, then a week later I find it at 6 to 6.5, I can adjust with what I mix up when making that water into feed from there

but if I came into ph8+ with foam on top of it then I`d just chuck the whole butt

hmmm yea i imagine there has to be a balance *somewhere*. My tap water has 5ppm silica in it, has to have been able to pass through all the processing and stuff so there's probably a chance you can "fix" the Si into solution to an extent... just not sure to what extent or... how lol
 

THE KONASSURE

Well-Known Member
Makes sense... maybe I'll just do a silica flush between rez changes. I've been doing a 24hr flush anyways, might as well run something in there- plus its good to keep something dissolved in the water during a flush- hypotonic water with no nutes can be hard on the plant (hence the fancy flushing solutions before harvest). The silicon probably works good as a 'filler'.
Silica and fulvic acid powder

not together but I like them in my water as they seem to add some bubbles and a bit of foaming, nothing like wetting agent will do but then airstones and wetting agent would be an issue

when I see more bubbles staying in the water and I see the water coming from the butts tap bubble and foam more in a good way I think "its holding more air that`s good"

I guess they gel that silica becomes if you get it wrong, when its spread over the whole mass of water it must just make it all a wee bit thicker meaning you get more air bubbles in the water ?

I think with the fulvic powder the bubbles are just the fulvic dissolving and such or maybe its reacting with something in the water ?

I found adding mono potassium phosphate, to my hydro systems kept them more stable over trying to feed light PK but obviously higher PK will do that in bloom cos the plants are taking it up

Also mono potassium phosphate I find a little heavy on the K now days I like to just add potassium sulphate to a 1-2-3 or a good a+b liquid feed now days
 

THE KONASSURE

Well-Known Member
hmmm yea i imagine there has to be a balance *somewhere*. My tap water has 5ppm silica in it, has to have been able to pass through all the processing and stuff so there's probably a chance you can "fix" the Si into solution to an extent... just not sure to what extent or... how lol
mix 200ml of 8% with 50L of water and then add it to your 200 to 400L res..... lol guess thats why GH put it in the pink one in the trio, lol
 

Yesdog

Well-Known Member
Silica and fulvic acid powder

not together but I like them in my water as they seem to add some bubbles and a bit of foaming, nothing like wetting agent will do but then airstones and wetting agent would be an issue

when I see more bubbles staying in the water and I see the water coming from the butts tap bubble and foam more in a good way I think "its holding more air that`s good"

I guess they gel that silica becomes if you get it wrong, when its spread over the whole mass of water it must just make it all a wee bit thicker meaning you get more air bubbles in the water ?

I think with the fulvic powder the bubbles are just the fulvic dissolving and such or maybe its reacting with something in the water ?

I found adding mono potassium phosphate, to my hydro systems kept them more stable over trying to feed light PK but obviously higher PK will do that in bloom cos the plants are taking it up

Also mono potassium phosphate I find a little heavy on the K now days I like to just add potassium sulphate to a 1-2-3 or a good a+b liquid feed now days
I've noticed some foaming with the FULMAX liquid- I noticed on my CO2 sensor that lots of CO2 was casually gassing off. Thinking it might have been the CO2 gassing off + the Silicon. The area around the CO2 bubbles will be really acidic, so some of the Si might have gelled around the bubbles.

Some bacteria/yeast also produce cellulose as a way of trying to defend themselves (by attempting to lock out oxygen via the film), that can cause a filmy gel/gunk on the surface (like a kombucha/vinegar SCOBY)
 

Yesdog

Well-Known Member
ooh right, and the fulvic powder is generally weakly ionized- meaning once its in water, it kinda violently tries to attach itself to a bunch of ions. Could be producing CO2, oxygen, or nitrogen gas. The liquid stuff is usually already ionized with Mg or K- that's why most of the liquids have an NPK value.

Hmm, also just ran into this from BioAg's research:
Fulvic acids are especially important because of their ability to complex or chelate metal ions and interact with silica.37 It has been shown that these interactions may increase the concentrations of metal ions and silica found in water solutions to levels that are far in excess of their assumed dissolution ability.38
Hmmm, so maybe its good to premix silica into the water first.... then apply humic acid? Maybe the other way around? If it really chelates it though, that's awesome! Trying to remember how chelate mix/prep work... I think you just mix the least soluble thing first.
 
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