Polyvinyl chloride, commonly called PVC, is an inexpensive material invaluable to reef aquarists for everything from plumbing to aquascaping. PVC is used commonly to connect the aquarium to the sump, refugium and additional saltwater aquarium components, but it also can be used to aquascape a reef tank. Building a rock reef with a PVC skeleton can create a structure that is solid and less at risk of being toppled by burrowing or large, boisterous animals.
Working With PVC
PVC is available commonly as schedule 40 PVC and schedule 80 PVC. For aquascaping a home aquarium, 1/2-inch schedule 40 PVC is sufficient. In addition to the PVC piping, you also will need a hacksaw or PVC pipe cutter, the appropriate solvent cement and a variety of fittings, including elbows, angles and tees. In addition, you will need a power drill and a drill bit appropriate for drilling through rock. All materials can be obtained easily at any hardware store. When working with solvent cement or drilling rock, be sure you are working in a well ventilated area, and wear safety glasses and gloves.
Designing the Reef
Before building the reef, inspect your rock and sketch out a rough design. The purpose of the PVC pipe in building a reef is to provide a skeleton for your rock work. While it is possible simply to stack your rock, using PVC to join the pieces together creates a more solid structure that is less likely to fall over. It also allows you to create some structures, such as caves and overhangs, that can be difficult to build securely with rock alone.
Drilling the Rock Vertically
Dry fit the rocks together outside the aquarium, making sure you like the reef design. Then, beginning with the highest rock, drill straight down through the first rock so you create a channel the diameter of the PVC pipe. Line up this channel with the rock below it, and then drill the next rock. Repeat until you have a single channel drilled from top to bottom. Insert the PVC pipe into this channel, mark it, and then remove and cut it to length. Slide the PVC pipe back into the channel to join the rocks together.
More Elaborate Structures
If your bottom rocks are large and stable, and each rock on top fits nicely against the one beneath it, you may not have to do anything beyond creating vertical PVC supports for your reef. If, however, you want to create more intricate structures, such as an overhang, you also may want to drill horizontal or angled channels in the rock, and then thread the rocks together using the PVC pipe. By cementing various fittings, such as elbows, angles and tees, you can create elaborate and secure structures that can tie the entire reef structure together.
Ret Talbot is an award-winning writer and photographer, as well as a lifelong freshwater and marine aquarist. He is the author of "Banggai Cardinalfish; A Guide to Captive Care, Breeding & Natural History" and "The Complete Idiot's Guide to Saltwater Aquariums." He is also a senior editor at "CORAL Magazine," the world's leading reef and marine aquarium magazine.