Timeless classics, these European toppers have retained their popularity and make a lovely decoration for your aquarium. This Aqua Della decoration is made of polyester resin. Completely toxin-free, it will not affect the biological balance of your aquarium. This decoration can be placed in both freshwater and saltwater aquariums. Caution: Do not use soap, all-purpose cleaners, or other cleaning products (e.g., hydrogen peroxide, thinner, or turpentine).