What's the best thing to clean lime build up? I had a repair man out to fix my dryer & he said use a little Borax in each load with my soap cuz I have hard water. Can this really be done lol & how much like 1 teaspoon or more? I've tried cleaning it with vinegar and or citric acid & the bowl has a bunch of what I assume is minerals in it. I'm going to save up for a new one since I got this used but just wondering if there is anything to really clean it well before then lol.