waterbear,

I'm an avid boater, all have been fiberglass, never added/checked calcium levels in the lake, and current boat is 17 years old and still solid . Therefore, I would tend to lean towards "load of bovine refuse". But that's just me. I've been "pool stored" (as Carl would say) one too many times. I would however believe the etching part but only under high pressure, like in a dishwasher so as far as "our" fiberglass pools, I think we're OK.