DIY Plywood Glass Aquarium

Determine the dimensions of your tank. Browse the selection of fish tanks available at your local pet store for ideas and think about the kind of fish you plan to have. Keep in mind that larger fish require more space.

Use an online aquarium volume calculator to determine how many gallons your proposed dimensions will hold. For your first tank consider using simple measurements, such as 14-by-48-by-14 inches, which will hold approximately 40 gallons.

Select the proper thickness of glass for your aquarium using an online aquarium glass thickness calculator. Glass that is 1/4-inch thick is appropriate for tanks 18 inches high or less and 3/8-inch or 1/2-inch glass is recommended for taller tanks. The length of the tank does not affect the thickness of the glass because braces are centered across the tank depth to support the extra length of large tanks.

Purchase a sheet of tempered plate glass and have it cut to the appropriate size by a professional in the store. The glass should be cut to a half inch shorter than both the height and length of your aquarium. You will only need one piece of glass cut because the rest of your aquarium frame will be constructed from plywood. If you are following the proposed dimensions you will need a piece of glass measuring 13.5-by-47.5 inches.

Cut panels of 3/4-inch AC exterior plywood to size using a table saw. Cut two sheets of plywood using the height and length dimensions for your back and front panels and cut two pieces using your height and depth dimensions for your side panels. Cut one piece using the length and depth dimensions to serve as your bottom panel. If following the example given you will need three 14-by-48 inch pieces and two 14-by-14 inch pieces.

Cut a 3-inch piece of plywood to the depth of your aquarium to be used as a tank top brace. Following the example given this piece would measure 3-by-14 inches.

Lay out all of the plywood on a flat surface and inspect it for flaws. Sand the plywood where necessary to smooth away blemishes and fill in any dents with wood filler. Allow the filler to dry completely before moving on to the next step. It may take several hours for the filler to harden.

Lay the bottom panel flat on top of a set of boxes or stanchions raised to the height of your tank. Apply a generous amount of waterproof glue to all four edges then press the bottom of the back panel into the glue along one of the long sides of the bottom panel. Position the back panel so that it is at a 90-degree angle to the bottom panel and the top edge rests on the floor. Screw 2-inch wood screws into the joint at 3-inch intervals.

Apply waterproof glue to the bottom edge of both side panels and affix them to the two short sides of the bottom panel copying the previous procedure. Secure the joints with 2-inch wood screws placed at 3-inch intervals.

Lay the front panel out on a flat surface and make horizontal and vertical pencil markings 2 inches from the left, right, top and bottom edges. Connect the markings with solid lines. The result should be a rectangular shape within a 2-inch border. Following the example given, this rectangle should measure 12-by-46 inches. Cut out the rectangle with a jig saw and sand the rough edges.

Apply a bead of waterproof glue to the exposed edges of the bottom and the two side panels and press the front panel into the glue, lining up the edges. Secure the joints on all three sides with 2-inch wood screws spaced at 3-inch intervals and wipe away any excess glue from the entire aquarium. Allow the tank to dry overnight.

Apply a thin coat of epoxy paint, also called epoxy resin, to all of the wood surfaces inside and outside the tank. If you want the inside and outside of your tank to be colored, select a tinted epoxy paint. Allow the paint to dry for at least 24 hours then gently sand the entire surface of the tank with 120-grit sandpaper, being careful not to remove the entire layer of paint. Apply a second thin coat of paint and allow it to dry for 24 hours. Repeat the process of sanding and repainting until you have 4 layers of epoxy paint. Allow the last layer to dry for 24 hours.

Sand down the edges and corners of the glass sheet to remove any sharp edges and clean the entire surface with aromatic hydrocarbon cleaner and a soft rag or paper towel. Clean the glass a second time with glass cleaner and a paper towel.

Lay the tank face down on a flat, level surface and, using 120-grit sand paper, roughen up the 2-inch border around the rectangular opening in the front tank panel. Apply a bead of silicone caulking around the 2-inch border within 1 inch of the edge on all sides except the top where it should be within 1/2 inch.

Lay the sheet of glass inside the tank over the rectangular opening so that the bottom edge of the glass rests snugly against the bottom panel. Press down gently on the glass to seal it and remove any air bubbles then apply a coat of silicone caulking around the edges, pressing the caulking into and under the glass with your fingers to form a tight seal. Do not wipe away any excess caulking.

Install the tank top brace by laying it across the top of the tank, as close to centered as possible. Use three 2-inch wood screws to attach one short edge of the tank top brace along the inside edge of the back panel and three more screws to attach it inside the face frame.

Apply a thick bead of silicone caulking to all corners and straight seams inside the tank. Smooth the caulking with your fingers and do not wipe away any excess. Allow the tank to dry in a warm place for at least 48 hours then fill it with water and check for leaks. If no leaks appear after 24 hours, then your aquarium is safe to use.