I purchased a pool that has black stains on the vinyl liner way ABOVE the water line.
I know that these stains have been there for years.

I have scrubbed & scrubbed... tried bleach, two different types of vinyl cleaner & vitamin C. - not one iota of difference.
my m-i-l- suggested that I try " VIM " ( bathroom cleaner)

Anybody know how to clean up old vinyl liners?