Sounds like it won't be a problem getting a bottle to work then. I have a 3-gal waterer for my dog & I know they make smaller 1/2 gal & 1-gal for cats. You could probably find a bottle at a pet supply store to fit & work if need be. CLR should work good in cleaning up the reservoir, then flush a couple of times. If the steamer happens to have a brass or copper lined reservoir it will look beautiful! Got home last night. Will have more to post later today but need to go pick up my dog, then go see if I need to pump water for the cows. Run some errands; be back later.