In the wild, plecos use caves for shelter and spawning. Since most plecos are nocturnal, caves give them a place to doze during the day. Additionally, a cave will help a pleco feel safe in an aquarium, and help de-stress wild-caught specimens.
Cut your PVC to the desired length. Remember to take into account the size of your pleco and the size of your fish tank. Make sure you know how big your pleco will get; some species grow to longer than 2 feet.
Cut the pipe lengthwise, creating a half pipe.
Trim off the edges of the pipe, angling them in toward the top of the pipe. This will make the cave mouth look more realistic.
Sand down all the cut edges. Take care you don’t catch yourself on the sharp edges and burrs. Regular sandpaper works well for this purpose.
Glue aquarium gravel or rocks to the outside of the PVC pipe. Completely cover the outside; you shouldn’t see any PVC pipe showing through. Use only aquarium glue, as regular glue may harm your fish.
Allow the glue enough time to dry. Follow the manufacturer’s instruction. Many type of aquarium glue release toxic chemicals until they fully cure.
Soak and rinse the cave thoroughly to remove any byproducts from the glue or dust from the rocks. Don’t do this in the fish tank.
- If it's not for a display tank, you don't have to decorate the cave. Plecos don’t mind exposed pipe.
- Food-rated ABS plastic can work as well as PVC, and since it tends to be dark it looks more natural.
- Wear proper protective equipment (safety glasses, gloves) when working with tools.
- Only use rocks and gravel from pet shops; other rocks and gravel can contain chemicals that are harmful to fish.