Whoa! Now that you mention it, our toilet does get a discolored ring around the water line in about a weeks' time, and that is a pretty new development. It's a fairly new toilet (2 years old, maybe) so it's not like it is old and scratched or anything. And we work from home so it's not like the water is stagnant in there for any extended amount of time. I hadn't associated the two events before.. thanks for sharing this (although I'm sorry that you are also experiencing this annoyance!)