Brown spots on fiberglass pool

If I'm not doing this right, I apologize profusely. I DID read the new member info. I don't have an answer to the problem; I want to add my question. I don't know how to start a new thread or even if that is the correct thing to do! Anyway, I have, in the last two weeks, developed brown spots on the sides of my fiberglass pool. They're the size of a pencil eraser tip and they dissolve like dirt when I touch them. I'm used to having dirt on the bottom of my pool but dirt has never stuck to the sides of my pool, that I remember. I wonder if it is algae instead? My water is crystal clear and a test strip shows that all chemicals are within the recommended parameters. Thank you.

I've moved your post to a separate thread in the correct section.

I'm not sure what your spots are. If you can mail photos to poolforum AT gmail DOT com, that may help. And, you'll need to tell us WHAT the 'guess-strip' test results are.