Is fiberglass reptile safe?

[Vypyrz]

Thats what I was thinking, I just couldnt find very much concrete evidence. The more people I have with credible evidence that its safe, the more likely I will try it. I really want to make my own waterfall.

It sounds like you are pretty experienced working with it, probably far more than I am. You could always build a smaller experimental waterfall to see how it is, before building the one for the tank.