A coral reef is basically a complex structure a part of which is living and other features result from the live segment. Carbonate and mud create a habitat for mangroves and sea grass. Algae trap and plants accumulations create the reef complex. Surf and storms pile up to make fragmental material on the beaches and shoals develop into islets of cays on the top of the reef. Most reef corals are colonial. There are different types of roulette corals found at different locations and our Coral Online Help would surely help you find more about them.
A coral reef is generally facing the open sea. The fore reef is towards the sea and it descends into the water by the material derived from the reef. There is a shallow platform behind the fore-reef edge created out of dead area of reef framework and colonized by algal mats, sea grasses, and mangroves. Living framework patches are also found. If there does not exist an immediate adjacent landmass, the reef again descends into deeper water into the leeward side. Live reef frameworks are typically found on the slope as well. You can take advantage of the Coral Online Help for any concerns you have.