How to get rid of dark brown stains in toilet?

I need to get rid of calcified dark brown stains in the bottom of a toilet. I poured borax and vinegar in it and let it sit, and it allowed me to peel a little of it off, but that's it. I also tried bleach, which did nothing. Would something like Limeaway work?

Anonymous2021-04-07T06:59:47Z

Use spirits of salt (dilute hydrochloric acid) which you obtain from a chemist. Follow instructions carefully and avoid inhaling fumes. That dissolves the limescale which is what the stain is in.