anyone else wipe their lp tanks?

Im have a bit of compulsive disorder and like to keep things clean. So before we roll out its waxed and polished every time. Even though nobody really cares how dirty their lp tanks are; I do. Im having a heck of a time trying to keep it clean as the tank itself is exposed to the undercarriage of the rig. If anyone out there have any pointers to keep it clean or product recommendation to get all the road grime off I'd be happy to hear about them.