The bathtub in my (rented) apartment has been discoloring over the past week or so. Previously, it had been fine. I'm just wondering what's going on here; it gets worse after it is used.
I have a picture, and you can see the grey patch and some discoloration off to the sides; when I touch the grey part, it feels a little different than the rest of the bathtub. The other discolorations feel the same as the rest of the tub, but they're a different color.
Can anyone tell me what's going on here, and what I can do to fix it, or if I'm making a fuss about nothing? Thanks for your help.