This stalagmite is an ornament from Aqua Della's Stalagmites series. These themed ornaments are standardized to recreate the desired atmosphere as faithfully as possible. This ornament is made of polyester resin. It is completely harmless and has no impact on the biological balance of your aquarium. The decoration is suitable for both freshwater and saltwater aquariums. Care instructions: Carefully remove the decoration from the box and rinse it with lukewarm water. Caution: Do not use soap, all-purpose cleaners, or other cleaning products (e.g., hydrogen peroxide, thinner, turpentine).