Plexiglass (acrylic) aquariums have several advantages over glass. They're light and difficult to break, and they provide greater viewing clarity. However, purchasing a commercial aquarium can be expensive. This is why many people build their own. If you do it right, making your own Plexiglass aquarium can be less expensive.
To build an aquarium, you'll need a good plastic supplier. Make certain you're choosing the right plastic thickness and dimensions. Heavier plastics are more expensive, but they can also withstand more pressure. Water is heavy, and tanks over two feet tall require plastic a half-inch thick or more.
Most plastics come in four- by eight-foot sheets. It's a good idea to choose an aquarium size that will fit well on this sheet to lower costs. Odd-sized projects can make it hard to use the sheet efficiently because of the dimensions of their pieces. In this case, you may need more than one sheet.
Most people making their own acrylic aquariums usually have their plastic cut for them. The supplier can do this for a small fee. It's important to make sure that the cuts are accurate. Double-check your measurements before giving them to the supplier. Let your supplier know that you are building an aquarium and that cuts must be extremely accurate.
When you pick up your material, take a tape measure. Don't accept any pieces that aren't within 1/16-inch of your desired size. For additional cuts at home, or to cut your own pieces, use a saber or jig saw and wear a particle respirator and safety glasses. Drill any plumbing holes using a holesaw, but make sure you wet the area. Otherwise, friction and heat may melt the plastic. Support your acrylic from below to prevent splintering.
Your plastic should come with a protective sheet attached to it. Don't remove it until after assembly. Just peel it back from the edges to keep it from being caught in the joints. Dry-fit the pieces together before cementing. Make sure they fit well with no visible edge gaps. Slightly inaccurate pieces should be flipped, if possible. Put the less-accurate cuts at the top of the tank, not the bottom or sides. Side and bottom joints are under the most pressure.
Ask your supplier for a few pieces of scrap plastic to practice your cementing technique. Use a high-quality aquarium-safe solvent cement–ideally a silicone-based one, which is more flexible. You can buy cement from your plastic supplier. Prepare the edges for sealing by smoothing them with a sharp object such as a knife, razor blade or file. Practice this on scrap, too.
Hold cemented pieces together using electrical tape or other low-tack adhesive tape. Use multiple pieces of tape along all edges. Surprisingly, most aquariums don't require clamps. Seal all joints, then remove the protective coating once the cement and sealant have dried. Your aquarium is ready to use.
G.D. Palmer is a freelance writer and illustrator living in Milwaukee, Wis. She has been producing print and Web content for various organizations since 1998 and has been freelancing full-time since 2007. Palmer holds a Bachelor of Arts degree in writing and studio art from Beloit College in Beloit, Wis.