Stains on my vinyl liner, doesn't brush off...

[callmedpit]

I'm having some staining on my vinyl liner that doesn't brush off. Any idea what's going on and what I should do about it? It was not there when the pool closed for winter. Here's some pictures:





The guy that built the pool for the orignal homeowner said the following...I wanted to be sure he was correct or not?

He says liner pools shouldn't stain at all, if there are spots they should brush off with a brush or with shock. If they do not its possible they are from a fungus living under the liner. He says in that case it can grow underneath the liner and show through, but you cannot treat it from above. Our chemical supplier says that if it is a treatable liner stain you can use "AscorbX" which is pretty much vitamin C to get rid of the staining. We have used vitamin c successfully on some concrete stains by literally just rubbing vitamin c tablets on the surface.

 

[pooldv]

Those are valid comments. More here about diagnosing stains, Pool School - Pool Stains

 

[Sseaman]

Magic eraser?

 

[pooldv]

What about it? That isn't recommended in the article.