Hi, Steemit!!!
Coral reef , rock formations occurring in shallow areas of tropical seas. They are created as a result of the slow accumulation of calcium carbonate, produced by numerous generations of marine polyps for protection from predators, for attaching to the bottom in counteraction to sea waves, etc. When a single individual dies, its coral skeleton remains, and as a result, the reef expands. The way in which corals grow and, consequently, the reef, largely depends on the depth, prevailing currents and temperature of the surrounding sea water.
have a nice day ahead !!!
@ teddy2