I am trying to figure out what this fixture/appliance in in the basement of a house over 50 years old in the Kansas City area. It's about 3 feet tall and maybe 18 inches in diameter and seems to be a cast iron or steel tank. It has no power source, either gas or electric. It's fed by a main house water supply pipe pipe and the water coming out supplies the home with both of these lines connected near the base. It has a threaded plug on top and on the side. The water in and out is cold water. The homeowner has no idea what it is and basically just wants it gone. Wondering whether this could be some sort of water filter? I took a pic of it but the file size was too big to post so I'm trying to work that out.