Here is how we installed a water softener in our well pump supplied home. We added 2 large filters before and after the water softener unit. The filter before the softener prevents well water particulates from entering the unit. The filter after the softener filters the softened water through a charcoal filter.
Water Softener: http://amzn.to/2svu3VQ
Filter Unit: http://amzn.to/2rWVWr5