I added a new toilet to my bathroom . It doesnt get flushed regularly being unused. A black tidemark appears at the water level in the pan, and treaks of blackish marks run down from the top. Does this indicate a problem at all?
I would't imagine so, it sounds like a rubber component inside the siphon which tend to perish slightly as they get older. As long as the toilet functions and doesnt leak then I would leave it.
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