Kno3

Allwissend

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Please consult chemistry websites or Wikipedia for maximum solubility of compounds. Also be aware that the solubility of one compound will be influenced by the other compounds added to the water, pH and temperature.

The maximum solubility for KNO3 is 316g/L at room temperature, so you will need to double/triple your total volume to be able to dissolve all the salt.

Hope this helps.
 

steve todd

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Thanks I made new solution for lowlightweekly
200ml to 55 g. Kn03 Dosing 40ml weekly,will give me 10ppm of n03
This will last 5 weeks

Cheers
 
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Julia Adkins

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Solubility depends in part on the form that your potassium nitrate comes in. Some is intended for being mixed in soil and is less soluble than others. You need a specifically water soluble form. Any solute has a saturation level and usually will only reach partial saturation unless the temperature of the water is increased.
 

Allwissend

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Solubility depends in part on the form that your potassium nitrate comes in. Some is intended for being mixed in soil and is less soluble than others. You need a specifically water soluble form. Any solute has a saturation level and usually will only reach partial saturation unless the temperature of the water is increased.

Hi @Julia Adkins, what do you mean by forms of KNO3 ? Which ones would be more soluble ? Do you refer to purity of the salt or other sources of N ?

To my knowledge, potassium nitrate is KNO3 as described here:
https://pubchem.ncbi.nlm.nih.gov/compound/potassium_nitrate#section=2D-Structure

Thanks I made new solution for lowlightweekly
200ml to 55 g. Kn03 Dosing 40ml weekly,will give me 10ppm of n03
This will last 5 weeks

This is for the 670L aquarium ? This is correct. Just to double check, the total volume of the solution is 200mL or ? So you add enough water over the 55g KNO3 to get 200mL solution.
 
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steve todd

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Yes for the 670l with anubais and discus. I used the Rotala calculator, lowlight weekly make a solution using 200ml and dosing 40ml weekly it said to use 55g KNO3,I then made 200ml solutions of p04,amgrow trace mix both dosing 40ml weekly
I

cheers
 
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Julia Adkins

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Allwissend, by form I mean whether it comes in a grade like flour or like granulated sugar. The chemical compound is the same, KNO3. The flour like product is not very "drop in water soluble". It works better when mixed in soil. Of course, it is the water that falls on the ground that allows it to become available to the plant roots. But it does not work well to make a solution or to use dry to dose a tank.
 

Allwissend

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Hi, that clarifies it.

With the very fine grade powders, it helps if you avoid the formation of "clumps". Mix well immediately after adding to the bottle of add at the filter outflow if dry dosing. Even when clumps get formed, if the solution is not saturated, KNO3 is easily dissolved in warmer water. Nothing like K2SO4 or CaSO4*2H2O, whatever grade ;)