This faithfully reproduced EBI decoration is made of polyester resin. It is completely non-toxic and has no effect on the biological balance of your aquarium. The decoration is suitable for both freshwater and saltwater Tip: Carefully remove the decoration from the box and rinse with warm water. Caution: do not use soap, all-purpose cleaners or other cleaning agents (e.g. hydrogen peroxide, thinner, turpentine).