Safest food grade diy ph down

Sulfuric acid is the most commonly used acid for pH down in agriculture, that means everyone from novice to professional.
 
It's a strong acid and very dangerous to handle phosphoric acid on the other hand is a weak acid and does the same job while not being a carcinogen. Untrained hands and an indoor grow can lead to accidents. Phosphoric acid is much safer in does not readily burn nearly as much as sulfuric. For a new grower or someone who's more concerned with safety with similar results to sulfuric acid phosphoric acid is the superior and safer choice while being more cost-effective even if buying a one gallon jug for $45
 
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Sulfuric acid is more dangerous than phosphoric acid in three way:

1 it is a known carcinogen

2 it causes Burns through hydrolysis as well as dehydration

3 it is at least three times as strong as phosphoric acid so the chemical and thermal burn are much more concentrated
 
You are beating a dead horse.

Sulfuric acid is the most commonly used, period. A high school student could understand this.
 
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No one's debating that it's the most widely used pH Down. The problem is it's corrosive and causes Burns through hydrolysis and dehydration as well as being a known carcinogen. Not only do you not list a dust mask( bare minimum for respiratory safety) as a necessary safety precaution you failed to inform potential users that it is a known carcinogen.further more in lieu of measuring spoons, a glass measuring cup should be used

this is the gas mask that 3m recommends for agricultural use of sulfuric acid
https://www.amazon.com/3M-Respirato...8&qid=1497169938&sr=8-6&keywords=6800+3m+mask
$157

now this is the gas mask 3m recommends for handling phosphoric acid:
https://www.amazon.com/Particulate-...F8&qid=1497170574&sr=1-1&keywords=3m+n95+mask
$4.99

https://r.search.yahoo.com/_ylt=A0L...uide.pdf/RK=1/RS=pBNO9dbEiCzt7Royh556ICXQTpU-

Again no one is debating the widespread use of sulfuric acid as a pH Down but phosphoric acid is just as good cheaper and safer and that is something that you can't debate
 

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I prefer hydrochloric acid/muriatic acid myself. Great source of chloride for your plants. Although, I sometimes use phosphoric acid.

Generally, the safest I've used is the nitrification of ammonia. Works great, and completely organic.
 
Agreed. Muriatic is available at any hardware or home center. Don't try to measure from a gallon bottle. Wear vinyl gloves, protective eyewear/sunglasses, and a gas mask, and transfer 1 ounce, using a small funnel, to an eye dropper bottle.
 
Father Ramirez said:
Agreed. Muriatic is available at any hardware or home center. Don't try to measure from a gallon bottle. Wear vinyl gloves, protective eyewear/sunglasses, and a gas mask, and transfer 1 ounce, using a small funnel, to an eye dropper bottle.
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I just pour it in, but I'm working with 1300+ gallons in my reservoir. It take about half a cup to 1-2 points pH.
 
I'd use the phosphoric acid before using hydrochloric acid.

Hydrochloric acid is a strong acid, but provides Cl, which the plant need very little of. At least too much chloride won't make your reservoir cloudy like too much phosphate can.

The best acid to use is nitric acid which is a strong acid and provides a source of N.
 
churchhaze said:
I'd use the phosphoric acid before using hydrochloric acid.

Hydrochloric acid is a strong acid, but provides Cl, which the plant need very little of. At least too much chloride won't make your reservoir cloudy like too much phosphate can.

The best acid to use is nitric acid which is a strong acid and provides a source of N.
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My target level of Cl is actually higher than you'd think, about 100-110ppm. If I use phosphoric acid, I'd have to add a bottle at a time, as it's generally too diluted, and very expensive. It'd also make my "P" off the charts.

Nitric acid would also make my N way too high, as my target for that is only about 20-30ppm
 
churchhaze said:
I'd use the phosphoric acid before using hydrochloric acid.

Hydrochloric acid is a strong acid, but provides Cl, which the plant need very little of. At least too much chloride won't make your reservoir cloudy like too much phosphate can.

The best acid to use is nitric acid which is a strong acid and provides a source of N.
Click to expand...

Never took into account hydro grows, organic soil is more my thing, that being said I did this write up for a safer pH down for new growers who use soil, but for hydro setups p shouldn't be too hard to control if k and trace are supplemented and flower nutes are dialed back
 
The reason why sulfuric acid is preferred over all other choices is that it does not interfere with the nutrient levels as the other acids do. Phosphoric acid can only be used in extremely small amounts, nitric acid is used to make bombs and isn't readily available, citric acid is a solid.

I've been successful in handling battery acid with no protective gear at all. With the right eye dropper I was able to use the sulfuric acid straight from the retail container as well. Best $8 I ever spent, a few drops and I was done. Amazon sells a 2lb container of flake potassium hydroxide for $8, with these two options you'll never break the bank with pH up or down (see sig).

Grow better bud, spend less money.

:leaf:
 
85% phosphoric acid is ~27% phosphorous, diluted down to 20% phosphoric acid that's ~3% phosphorous.
Most pH downs use phosphoric acid, I can't find a single pH down that contains sulfuric acid from the major hydroponic companies. Tons of results for pool pH Down and battery acid. A quick search of material safety data sheets and I found five Hydro nutrient manufacturers who use phosphoric acid in their pH Down.
 
I'm sure they like selling those 5 gallon buckets for $100. An $8 bottle that you'll probably never use all of doesn't make a lot of money for them.

If you want to overspend your money, go right ahead.

Some of us want to save that $100 for lights, or nutrients, or ventilation and odor control.

You make someone else rich, leave the rest of us to grow better bud for less.

:leaf:
 
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