My tenant left this for me. What’s the best way to get rid of lime and rust in a sink?

Prevent Future Stains
1. Wipe down sinks after every use to prevent mineral buildup.
2. Install a water softener to reduce the levels of calcium and iron in your water supply.
3. Regularly inspect and clean your sink to catch any new stains early.
By following these outlined methods, you can effectively deal with and prevent lime and rust stains, keeping your sink looking clean and welcoming.