Good or Bad?

[gwand]

That sounds about right—the calcium build-up is 100% a thing, so I can check that off the list. I am curious though...above, @gwand mentioned that they use spring water. I know there's a difference between spring, RO, and distilled water (can't remember specifics at the moment), but would they all work for the same purpose of diluting my water?

I measured GH and KH in several different brands of springwater. And the water parameters varied as you might expect by the water source. Since I was buying the springwater for a dedicated shrimp tank, I picked the brand where the GH was about 150 ppm.