No, you wouldn't have to replace anything but the head and probably the media. I like Clack the best. They are the new kid on the block, but are superior to all the others. They are not proprietary like Culligan, Kinetico and some others. Every softener guy in the US can buy them and get parts if needed. Problem is, they have a policy where they won't let their distributors drop ship their products for dealers so I couldn't send you one without first buying it then sending it myself. the shipping would get too high. The next brand in line is the Fleck. The Fleck 5600 with the meter is a very good head. As for the resin, it is all pretty much the same. It all works the same way, (ion exchange).