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
Zhongzhou Reef Zhongzhou Reef Zhongzhou Reef also known as Ban Than Reef and Centre Cay (; ) is a small coral reef on the north edge of the Tizard Bank in the Spratly Islands, South China Sea. It lies east of ROC-occupied Taiping Island (Itu Aba), west of Vietnamese-occupied Sand Cay, and has an exposed area of approximately during high tide, and during low tide. It consists of an accumulation of seashells, sand, coral reefs and debris which forms a circular coral reef plate, surrounding the reef under the water, with a diameter of approximately . The reef is currently controlled by