Have you successful done this and had it hold water? If so what adhesive did you use?
I have some nice thick plexiglass it's already frosted and nearly already the right size. I would like to use it for tank dividers but I gathers it's hard to keep glued down with silicone. I have seen reccomendations of a product called Weld-on 40 on saltwater forums. I guess they make pumps and other equipment for thier tanks from acrylic and have to glue them down.
I do have glass from an old patio door it's just going to be more trouble. I am wanting the dividers to be watertight. I know about craft dividers they will be my plan B. I'd prefer the fish not share tank water. Plus the cost is cheaper for me. I have enough of everything already.