Check my math - DIY KCl dosing

trevorhiller

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I want to dose some Potassium Chloride. I ordered 227 grams from LoudWolf and mixed 150 grams of it into 850 mL water for a stock solution concentration of 78.67 grams of K in 850 mL for 92.55 mg K / mL

Formula weights I used were:
KCl- 74.548 (100%)
K- 39.098 (52.44%)
Cl- 35.45 (47.55%)

I used the dilution calculator here:

So about 25 mL should raise the volume of my 63 gallon / 238 Liter aquarium by 10 ppm. Does this look correct?

I'm trying to reteach myself high school chemistry, so if you have any tips or corrections I'm all ears!

Screen Shot 2022-12-08 at 7.34.20 PM.png
 

t5Nitro

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Did that dissolve well for you? I put 113.5 grams KCl powder into 500 mL of RODI by weight and it looks supersaturated.

Just to bump an old thread others might find useful in forum searches. I might just dilute it into a total 1 liter and double my daily dose.
 

Randy Holmes-Farley

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My first use of my new diy archive. lol

I show how to use a calculator for K from KCl here:

 

Randy Holmes-Farley

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Did that dissolve well for you? I put 113.5 grams KCl powder into 500 mL of RODI by weight and it looks supersaturated.

Just to bump an old thread others might find useful in forum searches. I might just dilute it into a total 1 liter and double my daily dose.

Wikipedia gives these solubilities:
27.77 g/100mL (0 °C)
33.97 g/100mL (20 °C)
54.02 g/100mL (100 °C)

so your recipe should dissolve. Try warming it
 

biom

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Did that dissolve well for you? I put 113.5 grams KCl powder into 500 mL of RODI by weight and it looks supersaturated.
Just be aware when dissolving bigger amounts - there is a chance final volume of the solution to be more than 500 ml and to have less mg per ml than calculated.
 
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trevorhiller

trevorhiller

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Did that dissolve well for you? I put 113.5 grams KCl powder into 500 mL of RODI by weight and it looks supersaturated.

Just to bump an old thread others might find useful in forum searches. I might just dilute it into a total 1 liter and double my daily dose
Yes that dissolved ok for me, it took a lot of mixing though. I wouldn't make it more concentrated because I think you'd have to heat it to keep it in in solution. Even with mine there are occcassionally particles settled on the bottom of the bottle and I have to shake before dosing it.
 

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