Made from premium resin and plastic, durable, non-toxic and pollution-free. Absolutely safe for the fish you’ve loved. Real motion pneumatic ornaments provide entertaining action while aerating your tank. Great ornament and really fun to watch while setting up. As the diver floats, the treasure chest opens and closes to reveal the treasure inside, more alive and active Ideal for various aquariums and safe for both freshwater and saltwater, your freshwater fish or saltwater fish can play with their new toy.