Remove rust from bathtub,
I use Barkeeper's Friend spray. Spray, let sit for 5 minutes, and then clean.
clr for bath
clr for kitchen, bath
Lysol Lime & Rust Remover Toilet Bowl cleaner, comes in a black squirt bottle. Scrub with Scrub Daddy or Mr. Clean Magic Eraser.
Bar Keeper's Friend works too.
Vinegar and lemon juice will begin to eat away at the rust, using the natural acidity of both ingredients. To add more fire power to this solution, sprinkle a little baking soda and allow it to set on the rust for at least an hour.
CLR will do the trick near instantly.
If it’s bad around the drain hole, you’ll need to seal it with Rustoleum’s Rust Inhibiting Paint, not just regular Rustoleum.
I spray it in the cap first, then use a camel hair brush to carefully paint it and put a lot on.