Blue iQuatics Indo Reef Special Box S-1 (2 pcs.)Ships UPS Free! Box S 1 contains pieces #5 and 21. These calcium carbonate based rocks are crafted using molds made from some of the finest pieces of live rock found on actual living reefs. Each piece is then hand painted using a safe, non toxic paint to give it a unique appearance. We have been using them in our store's display since 2022, and in our servicing accounts for many years before that. We absolutely love this product. It is very porous and