We have a water softener at a cottage that is used only in the summer. Over the winter, we noticed rust in the water of the toilet tanks and our first load of laundry was dingy. The softener had run out of salt some time during the winter. Have we ruined our water softener by letting it run out of salt? If we add salt and let it regenerate, will it continue to soften our water? Is there something more that we can do to control the rust in our water?