so the glass is the structural support holding up the Aquapod? If it breaks would the pod falls into the tank? I don't think I'd trust small panels of glass for structural support, too easy to be compromised with any stress, shock, impact, especially if its going to have a hole cut out of the middle, sounds extremely weak for glass. Acrylic will be lighter, stronger, and easier to remove/handle. Since the bulb is going to be over the cut out, there is no way it could melt the acrylic.
just my 2cents!
Cheers,
Josh