How do I remove stains from bathtub that appears plastic covered.

It's Probably fiberglass. I would start with scrubbing bubbles. Spray, let sit for a while, then lightly scrub with nylon scrubby (white or pink). Rinse and repeat immediately. If this doesn't work, fill tub deep enough to cover stain. Add a few tablespoons bleach. Let soak for an hour

What sort of stains are they? Are they from water marks? They are very difficult to shift. Maybe try a paste of bi.-carb soda and place on stains and see what happens. If they stains are really bad, what I did years ago when I had an enamel bathtub that had seen better days, was get a tradesman to put over the old tub, an 'inner bath' ie fitted perfectly over the old tub. Check with your local bathroom specialists, and see if this option is available to you. There is also the option of having it re-coated (spray painted). Good luck.

Magic eraser

I haven't tried this. Lets see what happens. Thanks.

I'm totally agree with Gabrielle Falk, bicarbonate soda is the best option as I've also tried this & it really works

Hello, hope this helps you out.

https://www.bondcleaninginbrisbane.com.au/how-to-remove-stains-from-acrylic-bathtub/