That's crazy. Hope it turns out OK! I would think if there's fiberglass that close to the tank and it's an open top it's already in the tank and wouldn't sweat it.Wish me luck everyone, my shark got scared by a noise last night and jumped out of and behind the tank luckily I watched it happen but I've had him for almost two years and I'm hoping he makes it. Was out of the water to almost a minute while I tried to retrieve him. Also in my rush to throw him back in the water I didn't see he had fiberglass insulation on him which I'm hoping didn't contaminate my tank. This hobby is so frustrating sometimes