Question for the Chemists

[k9outfit]

Yet another question about GH... :roll:

I'm considering trying a "pillow" the LFS recommended, to soften my liquid rock. The pillow works by exchanging Ca & Mg ions, for Na I believe it is? So, if my hardness is 10 dGH - 179 ppm, would Sodium levels also end up being 179 ppm once there has been a 100% ion exchange?

Guess what I'm trying to get at in a confused sort of way, is what levels of Sodium would there be (theoretically) once the "pillow" has worked it's wonders?

[markdynamite]

Calcium Carbonate, CaCO3 and Magnesium Carbonate, MgCO3 undergoing an exchange would provide you with Sodium Carbonate, Na2CO3. The ionic charge of Calcium is +2, Magnesium is +2, Sodium is +1, and Carbonate is -2. Therefore you need 2 sodium ions for every calcium or magnesium ion in the exchange. So after a 100% replacement, your sodium levels are going to be 2 times 179, that is 358 parts per million.