Coral reef a protective area, or it may lie between the reef and the shore, and in this case is a flat, rocky area. Fish tend to prefer it when it is present. The reef lagoon is an entirely enclosed region, which creates an area less affected by wave action and often contains small reef patches. However, the "topography of coral reefs is constantly changing. Each reef is made up of irregular patches of algae, sessile invertebrates, and bare rock and sand. The size, shape and relative abundance of these patches changes from year to year in response to the various factors
Mesophotic coral reef and a crossover of coral species between the two is common. It is thought that these corals could be used as sources for reseeding shallow water coral species. Mesophotic coral reef A Mesophotic coral reef, from "meso" meaning middle and "photic" meaning light, is characterised by the presence of both light dependent coral and algae, and organisms that can be found in water with low light penetration. They normally grow between 30 to and up to in tropical and subtropical water. The most common species at the mesophotic level are corals, sponges and algae. The corals ranges can overlap with