Ken,

Without knowing how hard your water is and what model number you are
using it is difficult to guess how much salt you should be using. But, yes,
80 lbs/mo is excessive. Regenerating twice a week is probably also
excessive. I'd be surprised if you need 40 lbs/mo. Talk to your service man.
he can tell you how much salt you should use per regeneration and how often
you should regenerate.

Good luck,
Dave M.