Now my tub has been since when my parent's build the house, it is a stand-in tub, ~44 years old. I do not use it at all for baths whatsoever, I learned from a friend of mine about the magical eraser, I tried it a few times when the spray and wait kind of cleaner, but the yellow stain has been still there forever, it has only one user, well me, and my belly hahaa So I am wondering how to really use some sort of cleaner to have it like brand new... Any suggestions will be really nice