u/DumbQuestions000

Moved into a secondhand apartment a few months ago, and there was a big stain at the bottom of the toilets, likely from standing water as the place was vacant for half a year.

Managed to get rid of the stain completely on the other toilet, and this one is a big improvement from what it was before but I still can't get it off! I've been scrubbing at it with a pumice stone almost daily for a few minutes, but now I don't even know if I've scrubbed too much and made a dent in the enamel, while missing the actual stain.

Help please!