Calcium Source and others...

[SunnyOptimism]

Thanks for the prompt reply. I did see the reply on my other post as well - sorry for the hijacking. I was thinking someone who had found this thread may benefit as well but then wondered if an older one like this would be viewed. Sorry for double post.
Would it be best to delete my post here - if I can even do that?

I wouldn't delete anything (not even sure how to do that). Just leave it as-is.

[SunnyOptimism]

Just to comment on Calcium deicer blends, the sodium and potassium chloride will do nothing for your CH and the magnesium chloride would be bad for your pool surfaces (Mg can scale out and discolor plaster) and bad for SWCG pools. If you have to raise your CH a lot, then you need to know exactly how much of those other components you are adding to your water.

[chem geek]

It would take a heck of a lot of magnesium to scale out. Typical hard water has both calcium and magnesium, but the solubility of magnesium carbonate is far higher than that of calcium carbonate. As for SWCG pools, the main issue is with splash-out of magnesium sulfate that has a high re-crystallization pressure so can do the most damage to unsealed soft stone or concrete. Even so, if the magnesium were a minor component of the ice salt, I wouldn't worry about it.