Potassium Nitrate dosing

Reefology1

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Here's my standard recipe for potassium nitrate, and it can be adjusted easily up or down in concentration, as needed:

Dissolve 10 grams potassium nitrate in 1 liter of fresh water. That 10 grams contains 6.14 grams of nitrate, so that solution is 6,140 ppm nitrate.

If you add 1 ml of the solution per 2 gallons of tank water volume, that will boost nitrate by 0.8 ppm nitrate.

As a rough estimate, 10 dry mL of powder weighs about 10 g.
Hi @Randy Holmes-Farley, I'm hoping you can clear something up for me. I'm trying to mix up some Kno3 and from numerous sources I've seen that Kno3 contains roughly 39% potassium and 13.7 nitrate. now from the quote above, that would suggest there is actually 61.4% nitrate in Kno3?

Thanks in advance.
 

Cory

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Hi @Randy Holmes-Farley, I'm hoping you can clear something up for me. I'm trying to mix up some Kno3 and from numerous sources I've seen that Kno3 contains roughly 39% potassium and 13.7 nitrate. now from the quote above, that would suggest there is actually 61.4% nitrate in Kno3?

Thanks in advance.
Heres what i found:

Nitrogen 13.854%
Oxygen 47.474 %
Potassium 38.672 %
 

Cory

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taricha

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I've seen that Kno3 contains roughly 39% potassium and 13.7 nitrate. now from the quote above, that would suggest there is actually 61.4% nitrate in Kno3?

As Cory said above, KNO3 is 61.4% nitrate (NO3) - which means KNO3 is 13.7% nitrogen (N).
 

Randy Holmes-Farley

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Hi @Randy Holmes-Farley, I'm hoping you can clear something up for me. I'm trying to mix up some Kno3 and from numerous sources I've seen that Kno3 contains roughly 39% potassium and 13.7 nitrate. now from the quote above, that would suggest there is actually 61.4% nitrate in Kno3?

Thanks in advance.

That is a very old quote and I no longer support potassium nitrate dosing since better options are readily available. Food grade sodium nitrate is my recommendation since potassium nitrate dosing risks excessive potassium unless you monitor it closely. Calcum nitrate is also good, but hard to find adequately pure.
 

KStatefan

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If you are interested in the math behind @Cory figures above.

1666784956318.png
 

Randy Holmes-Farley

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Sorry, Im a little confused here and hoping you can clarify. If N=13.85% mass, how is No3 61.33%?

In short, nitrogen is 13% of the solid, and oxygen is 47%. Since nitrate (NO3-) is all of the nitrogen plus all of the oxygen, it is more than 60% nitrate by weight.
 
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