# Difference of calcium as carbonate, chloride or sulfate?



## dawntwister (Sep 29, 2007)

Anybody know the difference of calcium in carbonate, chloride or sulfate form?

I googled for some time to find the difference. All I found is that carbonate is the solid form of calcium and calcium is need for the cells of plants.

Also what is the difference of potassium in chloride, 
nitrate, phosphate, or sulfate form?


----------



## Revan (Dec 26, 2005)

Calcium carbonate (CaCO3) is used to add Ca++ and to raise the alkalinity (KH). The CaCO3 have a very bad solubility and when you add it to water it raises the pH value because it consumes CO2.
CO3-- + CO2 + H2O ---> 2HCO3-
The solubility of CaCO3 became a little better in the tanks in which there is a good CO2 concentration (20-30mg/l)

Calcium Cloride (CaCl2) is used to add Ca++ and also add Cl-.
Cl- is a trace element essential to the plants but in very small amount. It is better to avoid to have too high concentration of Cl-. CaCl2 have a good solubility.

Calcium sulfate (CaSO4) is used to add Ca++ an also ad SO4--.
SO4-- contain sulphur (S) that is an element needed to the plants.
CaSO4 have a fairly good solubility. SO4-- ions generally don't cause any issue also at fairly high concentrations.

Potassium cloride (KCl) is used to add potassium (K+) that is an element needed by the plants in large amounts (and also add Cl- ions)

Potassium Nitrate (KNO3) is used to add nitrate (NO3-) and potassium (K+). NO3- ions contains Nitrogen (N) that is an element used by the plants in large amounts.

Potassium phosphate (KH2PO4) is used mainly to add PO4--- ions. PO4--- ions contains phosphorus that is an element used by the plants in large amounts. 

If you don't know very well all of these salts and the amounts need to the plants of each of these elements I suggest you to use methods that have proved to work well like tom Barr's Extimative Index or Edward's PPS or PPS pro.

Best regards


----------



## hoppycalif (Apr 7, 2005)

The calcium ions used by the plants are the same whether they were added as Calcium chloride, carbonate or sulfate. It is the second half of the salt - the anion part that is different.


----------



## dawntwister (Sep 29, 2007)

I googled potassium sulfate in aquarium and found more info on Cations and Anions. Beforehand had googled calcium sulfate and didn't find info that I could understand.

From info I gather dry ferts are sold with cation and anion suplement to create a balance. Is this correct? 

Potasssium sulfate sold as product for adding potassium; thus must have more potassium than sulfate. Is this correct?


----------



## hoppycalif (Apr 7, 2005)

dawntwister said:


> I googled potassium sulfate in aquarium and found more info on Cations and Anions. Beforehand had googled calcium sulfate and didn't find info that I could understand.
> 
> From info I gather dry ferts are sold with cation and anion suplement to create a balance. Is this correct?
> 
> Potasssium sulfate sold as product for adding potassium; thus must have more potassium than sulfate. Is this correct?


No, it isn't correct. When a salt is dissolved in water it disassociates into ions. Potassium Nitrate, KNO3, for example, disassociates into K+ ions and NO3- ions. The water it is dissolved in plus the salt is then a mix of ions, with as many positive charged ions as negative charged ions. The plants take the ions they need, whether positive or negative. But the water continues to have equal amounts of negative and positive charged ions. This can only be if the plant exchanges some other ion for the one it takes away. That, presumably, is H+ or OH-, which are the ions water is made of. (I'm in over my head here! HELP!)


----------



## dawntwister (Sep 29, 2007)

Well, I think I will contact Rex Griggs and ask about the dry ferts he is selling.


----------



## TimboJones (Feb 29, 2008)

Dawn whats the problem are you offended by hoppycalifs darwinian avatar?

He's a legend on this site, you're not.

I ask God for guidance daily. But this is the first and last time I will advertise it on a planted tank site!

Loose the signature its inappropriate here. Gods will takes place every second of ever day. The ugly and the sublime open you're eyes take a look around.

If anybody thinks I'm reading between the lines sorry, buts thats what I do. And my clients pay $750/hr.


----------



## hoppycalif (Apr 7, 2005)

Timbo, dawntwister and I have a very good relationship. I think you read something between the lines that was just dark fibers in the paper. Darn cheap paper!


----------

