The location in which Coral community’s commonly grow is often very restricted, as most coral communities can be typically found in shallow or deep water and relay on a consistent ocean temperature, most of the reefs, with a few exceptions can be found in tropical and semitropical waters, between 30° north and 30° south latitudes on a world map.
Shallow water coral reefs occupy approximately 284,300 square kilometres of the sea floor (less than 1%). Reef-building corals prefer clear and shallow water, where lots of sunlight filters through to their symbiotic algae. It is possible to find coral reefs at depths exceeding 91 m, but reef-building corals generally grow best at depths shallower than 70 m. Other factors influencing coral distribution are availability of hard-bottom substrate, and the presence of species that help control macro algae, like urchins and herbivorous fish.
Mesophytic coral is a term that literally translates to 'meso' for middle and 'photic' for light, it’s ecosystems are typically found at depths ranging from 30-40 m and extending to over 150 m in tropical and subtropical regions. Mesophytic coral ecosystems are often considered to be an extension of shallow coral ecosystems and often share common species.
These ecosystems are characterised by the presence of corals and associated communities found at water depths where the light reach is very low. The fact that they contain zooxanthellae and require light separates these corals from being considered true deep-sea corals. Often the corals will grow in forms that allow them to get as much light as possible to support their feeding.
As for Deep-sea coral communities they often thrive better on continental shelves and slopes all around the world, sometimes thousands of meters below the ocean surface. Unlike the more commonly know tropical coral reefs, these corals inhabit deeper waters on continental shelves, slopes, canyons, and seamounts in waters ranging from 50 m to over 3,000 m in depth. A few species also extend into shallower, cold waters in the northern latitudes. Deep-sea corals are found in all oceans, including the Subantarctic. Like their shallow-dwelling relatives, deep-sea corals exhibit high biodiversity.
The oceans with the highest number of coral species with in them is that of the Indian & Pacific Oceans, To date, almost 800 species of reef-building corals have been identified, with new discoveries occurring each year. Of the known species, the majority are found in the Indian and Pacific oceans in an area known as the Indo-Pacific region, within this section of the ocean more then 600 species of coral can be found forming the Coral Triangle a region that encompasses the waters around the Philippines, Malaysia, Indonesia, Timor-Leste, Papua New Guinea, and the Solomon Islands, making this region the global hotspot of coral diversity.
An easy way to understand the main difference between that of warm and cold water coral is to refer to this chat that compares then main characteristics of both species and very simply explains how and where the two differ, this image can also be used as a teaching aid for others if you wish to reuse it.