High-quality biologically neutral rocks created for easy corals' fragging. Made of natural, quality materials of the highest porosity, they provide quick settlement of beneficial bacteria and other microorganisms. The addition of dolomite helps to stabilize key marine aquarium parameters such as pH and KH. The use of natural materials guarantees ideal conditions for the development of new life, which are coral fragments. These can be easily cut and combined, and placed anywhere on rock or sand.