On Thursday, August 1, 2019 at 9:41:19 AM UTC-4, wrote:
On Tuesday, January 20, 1998 at 3:00:00 AM UTC-5, Cliff Kaminsky wrote:
I have a white no-wax kitchen floor. The model is Mannington Aurora.
Last year I put a small mat down on the floor by the sliding glass
door. A few days later when I moved the mat, there was a rectangluar
purple stain under it. I removed the mat and the stain proceded to
spread and fade somewhat to its current condition as a pink half-circle
in front of the glass door. My impression is that it is some kind of
algae or mold. The stain seems to go deep into the linoleum; it's not
just on the surface. Has anyone else experienced this problem? Can
anything be done about it? Thank you for any help.

-Cliff K.
Ann Arbor, Michigan

I have the same problem and would love to know what to do about it.

Bleach?