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Hi all,
The OP didn't use CaSO4.2H2O
Doesn't really matter, the ions will dissociate and then precipitate if the solubility of possible compounds is exceeded . .... you will have a solution of [Ca](2+), [Mg](2+) and Cl- and [SO4](2-). The Ca and Mg no longer care they came from a Cl salt or a SO4 salt. The Ca2+ will then react with the available SO42- and precipitate out of solution.
That one. It is the <"common-ion effect">.

cheers Darrel
 
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Doesn't really matter, the ions will dissociate and then precipitate if the solubility of possible compounds is exceeded .

The screenshot posted suggested mixing CaCl2 and MgSO4 in a solution many thousands of times more concentrated than it would be in the aquarium. This issue has been discussed in a similar thread. If one manages to dissolve everything in the first place, you will have a solution of [Ca](2+), [Mg](2+) and Cl- and [SO4](2-). The Ca and Mg no longer care they came from a Cl salt or a SO4 salt. The Ca2+ will then react with the available SO42- and precipitate out of solution.

Further mixing these 2 with a carbonate or bicarbonate source only made things worse.

So when making remineralising solutions it is best use common cations to prevent the precipitation of Calcium Sulphate, calcium carbonate or magnesium carbonate, makes sense. So the problem would be resolved by dry dosing the whole tank when doing a WC or using Calcium Chloride and Magnesium Chloride.

Looks like I need to revise the making of remineralising solutions on the new IFC Remineraliser sheet to account for this interaction and precipitation of Calcium Sulphate, calcium carbonate or magnesium carbonate :thumbup: Do like a challenge
 
Just thought the obvious way to resolve this precipitation issue is to make two remineralising solutions, one for each salt, add one to tank mix it a bit, then other to bucket of water pop bucket water in tank
 
Just thought the obvious way to resolve this precipitation issue is to make two remineralising solutions, one for each salt, add one to tank mix it a bit, then other to bucket of water pop bucket water in tank

That's what I do - MgSO4 in one container, CaCl2 in the other.
 
That's what I do - MgSO4 in one container, CaCl2 in the other.
That's just what I was thinking :thumbup: The Potassium/Sodium carbonates and bicarbonates should be fine with the Sulphates as well I think. Which @dw1305 or @X3NiTH should help confirm. Glad all this was spotted before my side of the coding of the new remineraliser sheet gets passed over, I would of been put in the 'Dog House' by @Hanuman for a short while 😅
 
Hi all,
Potassium/Sodium carbonates and bicarbonates should be fine with the Sulphates as well I think
Yes, the carbonates/bicarbonates of group 1 (alkali metals) are soluble, basically all salts of sodium (Na), potassium (K) etc are soluble. A good general guide is the valency, salts <"formed from the monovalent ions"> (Na+, NO3-, NH4+, Cl-, NO3-, OH-, H+ etc) are highly soluble.

This means that potassium compounds (KNO3, KHCO3, K2HPO4, KH2PO4 etc.) are all soluble, but as soon as you mix the soluble calcium chloride (CaCl2.2H2O) with the, equally soluble, di-potassium phosphate (K2HPO4), you get the Ca++ ions react with the PO4--- ions to form insoluble calcium phosphate (Ca3(PO4)2).

The only way of retrieving the potassium chloride (KCl) would be to evaporate the liquid until nearly dry (when you will have exceed the solubility limit of ~ 340g / litre at 20oC).

large_solubility_rules_chart-mk-png-png.png


cheers Darrel
 
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you can never truly make a good GH booster in a solution, unless you use NO3, Cl based chemicals for Ca, Mg. anything that add Co3, So4 in the same solution will quickly react.

your best approach is to go with:
CaCl, MgCl, CaNo3, MgNo3 together if you want highly soluble GH booster solution
 
hello again zeus

I halved the grams you mentioned, I made 500 ml.

Powders I Use:

-Magnesium sulfate

-calcium chloride

-potassium carbonate

This mix gives me kh 1 - gh 4.

But I still couldn't get a clear picture.

Is this because of K2C03?
-


Magnesium sulfate and calcium Chloride will precipitate, that milky stuff is mostly Caso4 which isn't very soluble, even though most of the Mg would have been present in the solution which is highly soluble. but since you also added Potassium Carbonate, your solution truly contain mainly K, Mg and Ca are sitting at bottom precipitated as
MgCO3, CaCO3 and CaSO4.
 
-


Magnesium sulfate and calcium Chloride will precipitate, that milky stuff is mostly Caso4 which isn't very soluble, even though most of the Mg would have been present in the solution which is highly soluble. but since you also added Potassium Carbonate, your solution truly contain mainly K, Mg and Ca are sitting at bottom precipitated as
MgCO3, CaCO3 and CaSO4.
so thats what was happenning. makes sense.
 
so thats what was happenning. makes sense.
Ca deficiency are very rare because the plant need for Calcium isn't that high. The only time high calcium can be beneficial is if you dose high micros. It acts as a counter balance, especially if you dose high boron. Far as the plant goes, I was growing plant at 1 ppm Ca weekly.

Far as you adding egg shell, the calcium from it isn't available right away, it will release little by little as it dissolve.
 
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It is also important to remineralise higher if you keep shrimp, their requirements are a lot higher than those of plants in terms of calcium availability.

Mainly through the water column, but you can also supplement through food. It is why you will often see a specific dGH quoted for certain shrimp species, and most are dGH 5 and above.
 
Mainly through the water column, but you can also supplement through food. It is why you will often see a specific dGH quoted for certain shrimp species, and most are dGH 5 and above.
I seconds that. Fish and Shrimps rely on water column and food sources for Calcium and Magnesium. Shrimps have higher requirements and need a good deal of Ca to build their exoskeleton. Very high levels of Ca will on the other hand make the molting process more difficult for the shrimps. From the bit of research if done it appears the sweet spot might be around 25-35 ppm of Ca and 8-12 ppm of Mg. Roughly corresponding to a GH in the 5.5-7.5 range. My own shrimp tank sits smack in the middle at 30 ppm of Ca and 10 ppm of Mg.

Also, I provide all my Ca through CaSO4... I am not sure why not more of our Chemistry/Fertilizer experts recommend CaSO4 over CaCl2 ... The lower Solubility of CaSO4 is absolutely no issue if you add it to the tank or WC water in dry powder form as needed instead of making a premixed solution (where it will be very hard to dissolve of course). The benefit of CaSO4 over CaCl is a much lower net TDS (good for livestock) and avoidance of the excess Chloride which in large quantiles can be bad for our livestock as well. For instance to target 30 ppm of Ca with CaCl2 you get a staggering 53 ppm of Cl whereas with CaSO4 you "only" get 24 ppm of S. Thats a 29 ppm difference.

On a side note: I have tried using Ca Gluconate (an organic compound - essentially a sugar) as well, but it appears to cause adverse interactions in the amounts needed to reach 30 ppm. Small amounts of Mg Gluconante in combination with MgSO4 and Mg(NO3) is fine it appears, but I am in the process of figuring out if I can lower my CaSO4 usage (shave off some of the unnecessary S) and complement with a bit of Ca Gluconate.

Cheers,
Michael
 
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I am not sure why not more of our Chemistry/Fertilizer experts recommend CaSO4 over CaCl2 ... The lower Solubility of CaSO4 is absolutely no issue if you add it to the tank or WC water in dry powder form as needed instead of making a premixed solution (where it will be very hard to dissolve of course).

No good for me if I can’t strap it to an auto doser! 😉

avoidance of the excess Chloride which in large quantiles can be bad for our livestock as well

I don’t believe the levels of Chloride that would result from typical remineralisation are an issue?

On a sidetone: I have tried using Ca Gluconate (an organic compound - essentially a sugar) as well, but it appears to cause adverse interactions in the amounts needed to reach 30 ppm. Small amounts of Mg Gluconante in combination with MgSO4 and Mg(NO3) is fine it appears, but I am in the process of figuring out if I can lower my CaSO4 usage (shave off some of the unnecessary S) and complement with a bit of Ca Gluconate.

Have you considered Calcium/Magnesium Nitrate?
 
My own shrimp tank sits smack in the middle at 30 ppm of Ca and 10 ppm of Mg.
I am in the process of figuring out if I can lower my CaSO4 usage (shave off some of the unnecessary S)

Could you not just reduce the overall GH (and therefore less S)? I run my tanks at around half your GH (3-4ish) and have seen no issues with my shrimp.
 
I don’t believe the levels of Chloride that would result from typical remineralisation are an issue?
Right. and I don't know what the limit is. However, it all adds up in terms of TDS and ultimately osmotic pressure/stress which is my main concern.
Have you considered Calcium/Magnesium Nitrate?
Yes. and for my NO3 dosing I am using a combination of Mg(NO3), MgSO4 and Mg Gluconate. For the Ca, using Ca(NO3) wouldn't give me much leverage... you get a fairly low amount of Ca with Ca(NO3) compared to the amount of NO3. I am currently targeting 15ppm of NO3 in my shrimp tank.

Cheers,
Michael
 
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Could you not just reduce the overall GH (and therefore less S)? I run my tanks at around half your GH (3-4ish) and have seen no issues with my shrimp.
Hi @Nick potts , That is interesting. 3-4 is definitely the lower end of what I've come across so far... Not not say that lower GH is not possible if the shrimps Calcium needs are otherwise met by food sources. What kind of shrimps are you keeping? and what's your Ca ppm vs. Mg ppm.?

Cheers,
Michael
 

@MichaelJ

there is nothing wrong with adding CaSo4, most people don't like too much of SO4 in their water, SO4 is much safer vs Cl though when it comes to plants, shrimps or fish, Cl doesn't pose much threat unless its extremely excess.
Right. and I don't know what the limit is. However, it all adds up in terms of TDS and ultimately osmotic pressure/stress which is my main concern.

Yes. and for my NO3 dosing I am using a combination of Mg(NO3), MgSO4 and Mg Gluconate. For the Ca, using Ca(NO3) wouldn't give me much leverage... you get a fairly low amount of Ca with Ca(NO3) compared to the amount of NO3. I am currently targeting 15ppm of NO3 in my shrimp tank.

Cheers,
Michael
you also get tiny amount of NH4 coming from CaNO3
 

@MichaelJ

there is nothing wrong with adding CaSo4, most people don't like too much of SO4 in their water, SO4 is much safer vs Cl though when it comes to plants, shrimps or fish, Cl doesn't pose much threat unless its extremely excess.
Hi @Happi. I wonder if SO4 is much safer vs Cl though when it comes to plants, shrimps or fish why don't people like too much SO4 ? I totally get the solubility concern if you premix (which you could just as well avoid doing... I never considered premixing my Macro/remins as it seems to be marred in issues mostly related to solubility and adverse interactions - traces is a different story and I do premix those).

you also get tiny amount of NH4 coming from CaNO3
Interesting... I did not know. Do you know how much?

Cheers,
Michael
 
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