The Headhunter Mach 5 pump and Headhunter toilet are designed to work together. Why not use the pump? You gain nothing by trying to use city water pressure and the toilet will NOT work at less than design pressure. Mine works great and there is no reason I would ever try to not use the Headhunter Mach 5 pump. I have about 60 pounds of pressure all the time in my coach using the pump. I don't think you are going to get anywhere near that on campground / city water in most areas. Why mess with success?