The Cobalt Aquarium Breeder Cone is used by Discus, Angels, Clownfish, and other substrate spawners to breed. It is designed to be the right size for fish, as well as be easy to handle by hobbyists. The Cobalt Breeder Cone is made of natural stoneware, so it will not leach or break down. Measures approximately 9 x 4.5. Made in the USA.