For the size you're looking for, you can do acrylic or glass. Both need to be fully supported along all the edges (so bowfront needs a support that matches the bow of the tank) but acrylic requires the entire bottom to be supported rather than just the vertical edges. NAGA is a vendor here on the board, located in Annapolis, that does good work. I recommend sending him a PM. Since you want it to be viewable on both sides, you will definitely need a custom tank.