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Targeting Potassium

Hi all,
Oldguy said:
I think that calcium nitrate is a double salt of formula: 5Ca(NO3)2.NH4NO3.10H2O. It is typically made by reacting limestone with weak nitric acid and then 'neutralizing' with ammonia.
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That us a good point. If you buy <"it as a fertiliser"> - <"Nitrochalk"> it is very likely to be the double salt (calcium ammonium nitrate). In nitrogen terms it gives you more <"bang for your buck">.

cheers Darrel
 
Hi @hypnogogia, not sure if this is relevant for you, but if you're targeting low GH and very low KH, a good combination for the calcium part and KH is CaSO4 and CaCO3. The CaCO3 gives you the KH you need and reduces the amount of excess SO4. As Darrel mention, the solubility is limited especially for the CaCO3 but when it gets into a large body of water it's a non issue.

For instance in one tank I target:

Mg 5 ppm from MgSO4 (1.15 GH)
Ca 6 ppm from CaSO4 (0.9 GH)
Ca 3 ppm from CaCO3 (0.45 GH/KH)

for a total of 2.5 GH and 0.45 KH.

Cheers,
Michael
 
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MichaelJ said:
Hi @hypnogogia, not sure if this is relevant for you, but if you're targeting low GH and very low KH, a good combination for the calcium part and KH is CaSO4 and CaCO3. The CaCO3 gives you the KH you need and reduces the amount of excess SO4. As Darrel mention, the solubility is limited especially for the CaCO3 but when it gets into a large body of water it's a non issue.

Cheers,
Michael
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Hi, I’m targeting 5.5 dGH and 1 KH. Currently been using calcium Sulfate and potassium bicarbonate, but as I’m soon to start using calcium nitrate instead of potassium nitrate, I thought I might as well use the calcium nitrate to remineralise as well. Hasn’t thought of also using calcium carbonate to use even less potassium. I’ll be making changes slowly anyway. Thanks @MichaelJ
 
Oldguy said:
I think that calcium nitrate is a double salt of formula: 5Ca(NO3)2.NH4NO3.10H2O. It is typically made by reacting limestone with weak nitric acid and then 'neutralizing' with ammonia. Always a little careful about the ammonium ions and I dose over two days. I buy mine as prill for hydroponic use.
Have you considered also using magnesium nitrate. Mg(NO3)2.6H20. I got mine, also as prill, from a horticultural supplier to the top fruit trade.
It is possible to get high nitrate values this way.
Hate not having subscripts for chemical formulae.
You tank looks really good.
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I was thinking that looking at the composition from the table I posted earlier, but the molar mass provided threw me off, if it was Calcium ammonium nitrate, should be closer to 1000g/mol ?
Einecs and CAS codes also point to the right salt - what would be the best DIY way to check? Magnesium nitrate I considered before, but could not find small quantities, and if I did it was hilariously expensive...

My idea was to get all the macro elements independent from each other.

Matt
 
Oldguy said:
I think that calcium nitrate is a double salt of formula: 5Ca(NO3)2.NH4NO3.10H2O.
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This mutation prevails in agricultural practice because pure calcium nitrate melts at quite low temperature - 37 °C, I believe. It may easily melt and then freeze again, not a powder any more, but a white rock.
I keep my Ca(NO3)2 in fridge,
 
palcente said:
what would be the best DIY way to check?
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You have bought the fertalizer version, just as I have done. Pure calcium nitrate would not have any 'ammonium' component.
5[Ca(NO302] + [NH4NO3] + 10[H2O]
5[40+124] + [18+62] + [180]
820 + 80 + 180 total mass of compound 1080 (this line, the units could be mg or grams or any mass unit you fancy, it the beauty of relative atomic masses.)
Ca, 200 Ca: 1 Ca: 10ppm (mg/L)
NO3, 372 NO3: 1.86 NO3: 18.6ppm (mg/L)
NH4, 18 NH4: 0.09 NH4: 0.9ppm (mg/L)
Compound Mass, 1080 : 5.4 54pmm (mg/L) That is 54mg of compound will yield the above mg of ions. (Assuming that my sums are correct)
Scale up or down as required and factor in the net volume of your tank for a water change addition or to produce a stock solution.
Its what I use. I hope that this is of some value.

With reference to magnesium nitrate I agree with you. Small bottles expensive and postage from chemical supply companies even more than the product. Ended up buying a 25Kg sack just because it was the best bet. Just have to live a long time to get my moneys worth. The painting in the attic is falling apart as it is.
 
hypnogogia said:
but as I’m soon to start using calcium nitrate instead of potassium nitrate
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I personally never opted for CaNO3. Given the appprox 3:1 ratio of NO3 to Ca you're going to get a heck of a lot of NO3 for a relatively small amount of Ca. Which of course may or may not be an issue, depending on dosing regime.

Cheers,
Michael
 
MichaelJ said:
I personally never opted for CaNO3. Given the appprox 3:1 ratio of NO3 to Ca you're going to get a heck of a lot of NO3 for a relatively small amount of Ca. Which of course may or may not be an issue, depending on dosing regime.

Cheers,
Michael
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Ah, good point, thank you. I was never very good at chemistry. 😊
 
Oldguy said:
You have bought the fertalizer version, just as I have done. Pure calcium nitrate would not have any 'ammonium' component.
5[Ca(NO302] + [NH4NO3] + 10[H2O]
5[40+124] + [18+62] + [180]
820 + 80 + 180 total mass of compound 1080 (this line, the units could be mg or grams or any mass unit you fancy, it the beauty of relative atomic masses.)
Ca, 200 Ca: 1 Ca: 10ppm (mg/L)
NO3, 372 NO3: 1.86 NO3: 18.6ppm (mg/L)
NH4, 18 NH4: 0.09 NH4: 0.9ppm (mg/L)
Compound Mass, 1080 : 5.4 54pmm (mg/L) That is 54mg of compound will yield the above mg of ions. (Assuming that my sums are correct)
Scale up or down as required and factor in the net volume of your tank for a water change addition or to produce a stock solution.
Its what I use. I hope that this is of some value.

With reference to magnesium nitrate I agree with you. Small bottles expensive and postage from chemical supply companies even more than the product. Ended up buying a 25Kg sack just because it was the best bet. Just have to live a long time to get my moneys worth. The painting in the attic is falling apart as it is.
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I want to prepare this in a 75 liter tank and 500 ml bottle. How many grams of 1 ml 1 ppm should I use?
 
_Maq_ said:
Here you can see the mineralization:
View attachment 201865
The experiment was targeted at K:Mg:Ca ratios. The tank C was aimed at emulating "average Barr". The tank D was pretty the same, except half of the nitrogen was dosed in ammonium form. Please note, quite a lot of ammonium!
Here you can compare the tanks after 121 days running the experiment. Let me assure you that during whole period, algae infestation was never better nor worse in any of the tanks:
View attachment 201866View attachment 201867View attachment 201868View attachment 201869
Hygrophila corymbosa showed quite nicely what excess potassium looks like:
View attachment 201870View attachment 201871View attachment 201872View attachment 201873
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Hi
Hygrophila corymbosa showed quite nicely what excess potassium looks like?

True, K was 20x higher in C and D than in A and B. But what about also significantly higher conductivity, dGH, Mg, Ca, NO3, PO4, SO4 and Cl? Don't they have something to do with it?
 
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