The intricate development of a coral reef is both detailed and complex. The basic three formation stages of a reef development are the early forming Fringing reefs initiating close to the land, followed by the Barrier Reef forming a well defined zone separated from the land surface by a lagoon, and eventually a ring like formation of reefs encircling an entire lagoon create what is called an Atoll.
Within these basic stages are many sub-stages and variations under study such as a Patch reef with is often circular and formed within a lagoon, and an Apron reef similar to the fringing reef but more downward growth sloped away from a shore. A Bank reef will form in a more shaped linear crescent like form, where a Ribbon reef is more winding and narrow in shape, but both are unlike the Table reef which is often isolating in itself and similar to an Atoll without the lagoon.
Regardless of the type of formation the method of development is for the most part a common combination of science and nature. The first requirement is a warm sunny shallow ocean typically in the Tropics of the globe where the warm currents flow. Estimates have the coral reefs encompassing over half a million sea miles offering sanctuary to countless species, with the coral themselves being the originating skeleton-like structure to house the unique reef community.
The brightly coloured coral animal, polyps related to the jelly fish and anemones, are a limestone column shaped creature which attaches itself to each other and then to a surface though a tissue connection at with one end and grows out the other end to develop and entire colony which will eventually form a reef. They absorb the calcium in the sea and build themselves up through depositing a calcium carbonate, limestone, around their base as they grow. Within the colony as the coral polyps dies off their limestone skeletons continue to support the growing community. This intricate coral reef structure forms over time trapping rock, sand and grasses creating a home to organisms, fish and sea life. Both predators and prey exists within this sustainable bio-diverse system and structured food-chain within the reef.
Over a period of thousands of years massive reefs and even island have been formed by coral colonies. These coral reefs often called the rainforests of the sea, are not only a protection barrier for the shoreline from eroding wave action, but contain many known and yet undiscovered secrets to a self-sustainable ecosystem and life in the ocean waters.