In article , "Tim" wrote:
How often does a salt based water softener have to regenerate...and for how
long ? We have a rental home that has 2 adults. Based on the size of the
salt tank...I'd say it's a medium to large capacity softener. I've written
the manufacturer a couple times for a manual..but get no response.

Have you tried calling?

It's about 10-12 years old. Does it have to regenerate every night

For two adults, certainly not. Once every four days should be more than
enough. Try setting it to that, wait a week, and see if the water is soft
enough for you. If so, set to once every 7 or 8 days. Keep going, until the
water is too hard -- then set it to regen more often.

,...and/or for how long for each regen period ?

Typically the only other setting available is controlling how much salt it
uses each time it regenerates. You'll need a manual for that.