Safest food grade diy ph down

CobKits

Well-Known Member
Thank for the advice, how do you feel about general hydroponics pH down, specifically the formula
ive used it for years, its expensive. i made up some 30% w/w citric solution (plenty soluble) and literally use a few ml per 5 gal bucket- its not precipitating at that concentration and again its a chelator which is beneficial
 

Enigma

Well-Known Member
Since the op, I've amended the pH up with a 2 lb. flake potassium hydroxide from Amazon, $8. I've already explained it in the thread.

Sodium hydroxide is easy to use, first timers are recommended to use gear (safety) but I've handled the stuff outside with no gear with zero issues.

The same goes for sulfuric acid, no gear, plenty of uses, never had fuming issues.

It is interesting to note the same things you are concerned with are the same properties of the alternative acid you suggest.

It just happens to be your option is more expensive and will cause nutrient fluctuations.
 

dstroy

Well-Known Member
Solids precipitate.
Solids precipitate.

Care to elaborate on that?

What solids are you talking about specifically? You mean like when you add potassium silicate to full strength nutrient solution and stuff precipitates out?

You know that plant roots exude citric acid on their own to chelate (make soluble) insoluble metals, right? Guess I better keep an eye out for solids in my reservoir.

Not only that, but citric acid is relatively safe when compared to sulfuric acid, which is the point that these dudes are trying to nail home with you and you aren't listening. I'm not an expert at growing plants but I have a solid background in chemistry and electronics.

Sulfuric acid is not something that a hobbyist should mess with unless they have a good understanding of how dangerous it is.
 

Enigma

Well-Known Member
15 yr olds learn that in high school. We are talking basic knowledge.

Citric isn't a bad option for soil, sulfuric is the most commonly used and for good reason.
 

dstroy

Well-Known Member
15 yr olds learn that in high school. We are talking basic knowledge.

Citric isn't a bad option for soil, sulfuric is the most commonly used and for good reason.
You mean because it's readily available and cheap. Cheap being the most important part to someone trying to make a living off of something with a small profit margin, that doesn't mean it's the best.
 

applepoop1984

Well-Known Member
This kid is dumb as rocks, he has 30000 views on his diy sulfuric acid writeup, I wonder how much cancer/ burns that's amounted to. As far as the dust mask in reply to cob kits, read back a few posts I list the right respirator for sulfuric acid, happens to cost ~150$ ... Not exactly cheap. Solids precipitate lol...
 
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Enigma

Well-Known Member
Personal attacks, how elementary.

Stay on topic here, kiddo.

No accidents yet, but I'm sure there is someone out there that could hurt themselves with any acid. I remember watching someone grab a soldering iron from the hot end, not the brightest crayon in the box.

I've never needed a respirator. I can understand why you are so scared, this is new to you.
 

CobKits

Well-Known Member
Personal attacks, how elementary.

Stay on topic here, kiddo.

No accidents yet, but I'm sure there is someone out there that could hurt themselves with any acid. I remember watching someone grab a soldering iron from the hot end, not the brightest crayon in the box.

I've never needed a respirator. I can understand why you are so scared, this is new to you.
please circle back to the thread topic yourself- it was "safest" acid. sulfuric acid isnt even close, citric isnt anywhere near the same hazard class as sulfuric

just because you never had an issue doesnt make it "safe"

you are recommending a very strong acid to growers who have no idea what they are getting into.

safety is not about "fear" its about understanding the hazards and being save enough to avert the worst-case scenario that you never thought would happen like accidentally dropping the bottle etc. Everytime ive got burned by sulfuric it was that one time out of hundreds where it splashed when mixing. I could stick my hand in a bag of citric acid monohydrate powder and scoop it out if i washed my hand off reasonably promptly. i have scars years old from a single drop of sulfuric that i ran immediately to the sink to wash off. entirely different hazard class and you only need to consult the msds to verify this.

yes its widely used- in commercial agriculture where they are buying bulk and pennies matter

again ive got every acid under the sun at work and citric is my choice for home gardening, and phosphoric behind that
 
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applepoop1984

Well-Known Member
I intended to do this write-up for the benefit and safety of All Growers. I ended up learning a lot just want to say thanks to all those who responded with accurate information. Do you guys think it would be a good idea to do another write-up attempting to replicate the formula for General Hydroponics pH Down
 

Dumme

Well-Known Member
I intended to do this write-up for the benefit and safety of All Growers. I ended up learning a lot just want to say thanks to all those who responded with accurate information. Do you guys think it would be a good idea to do another write-up attempting to replicate the formula for General Hydroponics pH Down
GH is "Scott's Brand" I'm not a fan. ...and I believe its just phosphoric acid dilute.
 

applepoop1984

Well-Known Member
They use a blend of phosphoric acid at 10 to 30% citric acid in that stuff from the grow your own Crystal kits I forget what it's called. What about just mixing phosphoric acid 85% with citric acid or would that be dangerous
 

Dumme

Well-Known Member
Blue lab is set to 35% phosphoric acid in their pH down, and what I prefer, when used. Unfortunately, aquaponics and citric acid don't play well together. :(
 
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