Hi Lisa, If nothing else works you might try to disolve a few packs of denture cleaners in water in the pot. I use this to clean the hard water stains off of vases and have even had good luck using them in the tolit. It is a trick I learned a long time ago on a very nice cut glass vase that had water left in it too long. There was no way I could use anything that would scratch, so I tried the denture cleaner that works like Alka Seltzer.(posted 9673 days ago)Lots of luck Beth