I posted this in the "Stains" section, but no responses. I'm hoping that some of you guys do resurfacing & might be able to help out.

Anyway, we recently resurfaced our pool with the Marquis finish & upgraded to a bright blue color, but there are a couple of white stains on the surface of the pool. One is quite large & with the others you can almost see the outline of some footprints the contractors left on the bottom.

Any idea what this is or how we can gently remove them?