How to Make Artificial Coral. Coral are porous marine animals that live in the bottom of the ocean. Coral attaches to a strong foundation and then grows to create a coral reef. Coral is naturally vibrant and colorful. Making artificial coral is one way to add color to an aquarium. Artificial coral placed in the aquarium not only provides beauty but also provides variety for the resident fish.
Pour the plaster of paris into the coral mold. You can find coral molds in most craft supply stores. Use plaster of paris because other types of plaster or molding agents have toxic chemicals that can affect the fish.
Allow the plaster to dry completely. The time for this varies upon the size of the mold and the brand of plaster of paris you use.
Remove the coral from the mold. Take care not to break or damage the coral when removing it.
Paint the coral as desired. Coral is naturally bright with lots of pink, blue, orange, purple and green hues.
Allow the paint to dry completely before continuing. Apply more coats as needed. Allow each coat to dry before adding an extra coat.
Cover the coral generously with sealant. The sealant protects the fish from the paint and keeps the coral paint vibrant.