Try Barkeepers Friend in a dime sized area, following instructions on the container.

https://www.barkeepersfriend.com/

I agree. It looks like a rust stain. Try Iron Out Rust Stain remover.

Thank you all. I will try them all!

Have you tried a Magic Eraser? I was able to finally remove stains from our bathtub, when no cleaner would work. You can buy them at the Dollar store or grocery store.

Thanks for writing! Yes I tried Magic Eraser and Barkeepers Friend. I did the baking soda and vinegar thing too, left in for 24 hours and scrubbed and scrubbed! Still nothing! I really am thankful for all the suggestions. Still trying to get rid of it! I’m not sure if it’s rust, or maybe even hair dye...

If you are desperate at this point, I'd try a nail file, first a pretty smooth one, if that doesn't work, go up in roughness a bit.

There's another post re: fiberglass tub and shower stain remover and people swear by Easy Off Fume-free in blue can. It's few topics below yours.

If nothing works, you can apply a decorative decal or sticker over it. It would not be the first time such a cover-up was used. A strip of white electrical tape would work, too. Remove it while selling the house, of course, to be upfront about the condition.

You might try a commercial hair color remover (not the plain peroxide kind) available at drug stores.

I started a separate thread on the same topic (https://www.gardenweb.com/discussions/5064120/cleaning-method-for-tub) and someone was kind enough to direct me here.

I want to follow up and let others know what worked best for our situation. We got best results from using Barkeepers Friend and a pumice stone. Good luck!

Thank you. Thank you all. I have tried everything listed except the pumice stone and the oven cleaner. My next try is going to be the oven cleaner, and if that doesn'twork, I guess I will have to do as my husband suggests, which is "think of it as a decoration and get over it." I don't want to use the pumice stone, because I'm afraid of scratching up the acrylic jetted tub. So far nothing has even budged those stains.

Hi, I know this doesn't make sense,but use a toilet bowl cleaner called "The Works," we had a home with well water that stained our bath tub with this horrible orange rusty looking stuff, also our toilets, I bought "The Works" toilet bowl cleaner for the toilet and I could not believe my eyes,it took all the stains out, then I used a little on the tub and Gone!!!

If it’s acrylic DON’T use Bleach!! You can use Hydrogen peroxide, Clorox 2 or Oxiclean. I accidentally used bleach on my older porcelain tub ( which apparently used to be made with an iron component... big mess. It turned yellow and pasty and looked like it was caked in melting goo. I found this link that is helpful-

https://www.google.com/amp/www.instructables.com/id/How-to-turn-your-bleach-stained-red-bathtub-white-/%3famp_page=true

I am so glad I found this page......I have well water and the rust is awful even though I use the salt that is suppose to prevent this. Because I haven't been able to find anything to get rid of it...the build up was really bad practically my whole tub and wall was orange. I would clean it even though I could not get rid of it. So I tried the bar keepers friend which I had this whole time under my kitchen sink and boy did it work!!! I am amazed and little annoyed that I had it but never thought to use it. So thank you, thank you, thank you and my tub thanks you!! :) I wish I had taken before and after photos.

I found a photo online...this is not my tub but it looked like this. Now it's so white and clean.....and it took me less than 30 minutes to do.

What did you