Weldon bonds acrylics and other plastics together. you can spill it on glass or metal all day long and it would never be more than an inconvenience. But acrylic to acrylic, that stuff is insane. It basically just melts the plastic, melting two plastic pieces together.
Silicone might hold the acrylic to the glass, but not with enough strength to hold a tank together.
If you want the tank, and it's got thick enough glass to be an aquarium tank, then you would be fine using perfectly cut glass baffles as Treeman suggested, and aquarium silicone.
I was wondering why that tank looked funny to me... It didn't have a brace..