Calcium line removal from fiberglass tile.

[TGMcCallie]

I had my pool remodeled and after the remodel which involved a lot of cement and cement based products, I have a white line all along where the water level is on the fiberglass tile. The walls are Polynesian Pool fiberglass and the tiles are
manufactured (molded) into the walls which look like they are real tile but actually fiberglass.

I think this is calcium because I can scrape it with my fingernails and it will eventually come off. I would like to know how to remove this easily and not damage the fiberglass blue tile.

Any help that anyone can give me will be appreciated. I have read about using sand paper but I am afraid that this will permentally damage the tile. I thought that maybe muriatic acid would work.

What do you think concerning removal of this?

Thanks

Tom

 

[pooldv]

It is scale. Enter all your test results into PoolMath and it will give you a CSI number. Keep it between -0.3 and 0 to avoid scale. More here, Pool School - Calcium Scaling. It will go away on its own, mine did. Or you can use some 1 to 1 muriatic acid to water and a brush to brush it off.