HarryS wrote:
We have a black stain on the bottom of a procelain bathtub. We thought
that this stain was mildew but our old tried and true solution to
mildew in the bathroom (a solution of 20% liquid laundry bleach that
will eliminate mildew stains from tile grout, tub caulk, etc.) didn't
even faze it. Scrubbing doesn't affect it. The stain doesn't cover
the entire bottom of the tub evenly, rather it's somewhat mottled in
appearance. It's a little rough to the touch. We live in Springfield,
MO and have seen a tub in another home with this same type of stain and
those folks couldn't get it off either.

Does anyone have any idea how it can be removed.


I have something similar in shower stall - right where we normally
stand. I thought it was likely soil/oil/crud from dirty feet, but has
been really difficult to scrub off. Some comes off with 3m and
detergent, but it is tough. I've used a lot of CLR, but didn't
concentrate on the blob when I used it. Wonder if the glaze can wear a
bit, allowing dirt to stick harder?