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pH Down Doesn't Actually Work?

Malvedes

Well-Known Member
In what scenario would you be adding a large volume of water to a small volume of acid.

If say, you were using sulfuric acid to acidify alkaline water, and you put the acid into a water tank first, and then added water. Or if you were to fill a lead-acid battery and pour in the higher concentrated sulfuric acid first, and then add water. Acids come in variable strengths. Vinegar and lemon juice being mild, some hot tub and pool chemicals being stronger and typically in dry acid form, and then the likes of common battery acid, which is typically strong sulfuric acid (it will burn you if you get it on your skin). Some industrial drain cleaners that I have used also have a high concentration of sulfuric acid in them. I used to dissolve sponges and mop heads with that stuff when I was a dishwasher for fun.
 

Drivejunky95

Active Member
Out of context but interesting nonetheless.

Ah the dishwashing days, dont blame ya having a bit of fun in the dishpit!
 

Barney86

Well-Known Member
Right, this was a confusing read lol. You're issue is that the nute solution ph is rising over time yes?
Few things, what total ppm are you feeding cos that sounds like a lot of nutes.
Secondly, liquid scillica is extremely high ph and will counteract the effects of phosphoric acid. Not sure about other ph downs but that s what I use. Scillica is Best used at around 50ppm. Any more than that and it will most likely cause the ph to rise over time. Leave some on your skin and youll see why a lot of it in a mix is a bad idea lol. It also boils if you mix it straight with phosphoric. Not something you want excess amounts of.
And finally, assuming your feeding the correct dosage, the ph of the pot will rise a little during veg and drop a little during bloom. To keep it stable you go in at 5.8 for veg and 6.2 for bloom. Always feed on the lighter side and always to run off and the ph of the pot will stay within range. Excess nutes in the pot will throw your ph off and it's nothing to do with the ph of the nutes. Just the build up of them.
 

Drivejunky95

Active Member
Appreciate the knowledge on silicone. Using 1ml of silica per gallon, 1.25 in bloom, added first, mixed and left for an hour. Target/total ppm everything in included is 575ppm, getting very close to early bloom.

Water's pH retention is high as it comes from a well.

Think what @The Dude Inhales was saying is using stored nute solution doesnt help as the nute elements interact with one another and hydrogen and raise the pH over time. I've been making gallon batches that last 4 feedings x4 plants but the pH increases the most after the first 24hrs.

What's really the pH end zone is how elements build up and interact in the medium's CEC.

I'll link a really interesting thread in a bit that basically says your water pH doesnt matter (it helps to manage it a little) because once it goes into your medium the CEC is what determines the availability of nutes to your plant. And that's the hardest to control because how do you monitor pH of elements interacting (outside of brute force flushing).
 
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Barney86

Well-Known Member
Appreciate the knowledge on silicone. Using 1ml of silica per gallon, 1.25 in bloom, added first, mixed and left for an hour. Target/total ppm everything in included is 575ppm, getting very close to early bloom.

Water's pH retention is high as it comes from a well.

Think what @The Dude Inhales was saying is using stored nute solution doesnt help as the nute elements interact with one another and hydrogen and raise the pH over time. I've been making gallon batches that last 4 feedings x4 plants but the pH increases the most after the first 24hrs.

What's really the pH end zone is how elements build up and interact in the medium's CEC.

I'll link a really interesting thread in a bit that basically says your water pH doesnt matter (it helps to manage it a little) because once it goes into your medium the CEC is what determines the availability of nutes to your plant. And that's the hardest to control because how do you monitor pH of elements interacting (outside of brute force flushing).
Yeah mate 1 ml per gal is about right. I'm 0.3ml per litre and that's 35-40ppm for my one, growth technology.
If your leaving nutes sitting then put an air stone in it and remember to give it a good mix again before you test it.
Ahh, hang on a second..your water comes from a well? That's mental lol. Are you like dunking a pale down a well to get water? Where do you live mate? bet the ppm on that is high a/f.
I'm blessed with our water. Only 48ppm from the tap and clean as it gets. Can you drink that water ok or you gotta clean it first? I know your situation is probably nothing like Im imagining but I'm really stoned and getting some funny images lol.
 

Barney86

Well-Known Member
Oh and I know some say do, some say don't. But personally I don't like using scillica during bloom.
I use a tiny, very sensitive res and it keeps the ph steady as a rock. I can't handle that as it's not meant to happen so I don't trust it. For simplicity sake though i can see why people like it. Absolute essential for veg though. Can go through hell and back with training and not break a sweat. Lovely stuff.
 

Drivejunky95

Active Member
Yeah mate 1 ml per gal is about right. I'm 0.3ml per litre and that's 35-40ppm for my one, growth technology.
If your leaving nutes sitting then put an air stone in it and remember to give it a good mix again before you test it.
Ahh, hang on a second..your water comes from a well? That's mental lol. Are you like dunking a pale down a well to get water? Where do you live mate? bet the ppm on that is high a/f.
I'm blessed with our water. Only 48ppm from the tap and clean as it gets. Can you drink that water ok or you gotta clean it first? I know your situation is probably nothing like Im imagining but I'm really stoned and getting some funny images lol.

Haha, oh no, drilled well, couple hundred feet down. It's high in arsenic but there's a filter that reduces it to drinkable levels per health regulations. 81 ish ppm but 8.5 pH and seems to want to stay at 8.5. I think an RO system will make it easier to change pH and have it stay (fingers crossed).

Air stone, heard about them being good for adding oxygen to water for your plants.

Nice! If people believe in using silicone that's a good sign.
 
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