DIY Frag Plugs

Adding coral to a home aquarium can help to create a natural environment for saltwater fish. Coral fragment plugs, commonly called frag plugs, can be made from a variety of materials and offer a substrate that coral attaches to for placement in the aquarium. The plug resembles a small one-legged table, and the peg at the bottom of the plug is designed to fit into a small rock crevice to secure the coral and protect it from falling over. Frag plugs can be purchased at aquarium supply stores. However, you can also make frag plugs at home using items that can be purchased at your local hardware store.

Things You'll Need

  • Small bag of cement
  • Plastic cup
  • Bottle cap
  • Pencil
  • Plastic tray
  • Sand
Show More

Instructions

    • 1

      Fill a 3-inch tall plastic tray with sand. Moisten the sand with a small amount of water and press the sand down with your hands until it is firm.

    • 2

      Make the mold for the plugs. Place a plastic bottle cap top- down into the sand. Press the cap firmly into the sand then remove to make a circular indentation in the sand. Use a pencil to push a 2-inch deep hole into the center of the circle. Repeat the two-step process to fill the sand tray with plug molds

    • 3

      Mix the cement in a small plastic cup according to the manufacturer's instructions, then mix in an additional 1 tbsp. of water. Continue to add 1 tbsp. of water at at time until the mixture has a soup-like consistency.

    • 4

      Use the plastic cup to pour the cement mixture into each plug mold. Let the cement set for 48 hours. Remove the plugs by gently loosening the sand surrounding the mold and lifting the plug out. Allow the plugs to dry for an additional 24 hours before use.