Can You Use Regular PVC Plumbing Parts in a Freshwater Aquarium?

Schedule 40 PVC pipe is safe for both freshwater and saltwater aquariums, provided it is clean and the glue is dry. It is often a good idea to rub the inside of the PVC pipe with rubbing alcohol to remove any grease, dirt and contaminates before using it for the aquarium (let the alcohol evaporate before running water through it). When using PVC for aquariums, there are a few tips to keep in mind.

  1. Schedule 40 Pipe

    • Schedule 40 pipe, the standard white PVC pipe, can be used for freshwater and saltwater aquariums. This class of PVC pipe works well for creating extra plumbing for connecting multiple aquariums or adding a filtration system. In addition to the pipes, there are screens, bends, caps and dividers that can be connected in various ways to create elaborate systems.

    Purple Primer

    • When connecting the PVC pipes, you will need to prime the inside of the joint and the outside of the pipes with purple primer. When dry, the primer will help the glue hold the pipes together. When wet, the primer is toxic to fish, so let it thoroughly dry before connecting it to the aquarium. The vapors of the primer are also toxic, so work in a well ventilated area.

    PVC Glue

    • Like the purple primer, PVC glue is toxic to fish when wet. When gluing the pipes together, prime both the inside of the connector and outside of the pipe, let the primer dry, then add glue to the same areas. Press the pipe into the connector, twist to spread the glue evenly, and hold firmly for about five minutes (otherwise the glue will push the pipe out). Before sending aquarium water through the PVC plumbing, let the glue cure according to the instructions on the glue's container (usually 48 hours). Once cured, the glued pipes are safe for freshwater and saltwater. Do not glue the pipe to the pump; you will want to remove it later.

    Unions

    • More than likely, you will want to take the plumbing apart to clean or adjust it later. Unions attach to each end of a pipe and screw together. They can be unscrewed later, without requiring you to turn the pipe, so the pipe can be separated. There is a rubber O-ring inside the union that prevents leaks. Do not glue the union together.