You can go to the Architectural Clearing House on Calgary Trail near Argyll Road for glass.
Also, go to Garf.org to the tank building calculator to determine the thickness of glass that you would need.
You can also get silicone for aquarium use at Home Depot and Rona. It comes in clear, white or almond lol. Just make sure its window and door silicone and not stuff designed for use in Kitchen and Bath areas.
Before building the tank, make sure you clean the edges of the glass with Vinegar. Use fiber tape (you know, that tape with what looks like strings running in it) to hold the edges together after you've put silicone between them. Let the silicone cure for a couple of days for full strength.
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32"x32"x20" Cube-ish tank
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