Adele ring. In mathematics, the adele ring (also adelic ring or ring of adeles) is defined in class field theory, a branch of algebraic number theory. It allows one to elegantly describe the Artin reciprocity law. The adele ring is a self-dual topological ring, which is built on a global field.
Real softeners generally last 20+ years EVEN on ludicrously hard water while the service life on a pre-built softener seems to be under 5 years (if you're lucky) on really hard water and lasting longer than that is a rare exception.
The more your softener regenerates the more salt you will consume. As for the salt level in the brine tank, you can let the salt get down to the point inside the tank where you can see the water just above the salt. When you see water above the salt, it is time to add more! Generally, you will add salt to your brine tank about every 8 weeks.