Coral reefs are often referred to as the \"tropical rainforests\" of the ocean because of their rich biodiversity and critical ecological functions, making them a key component of the global marine ecosystem.
Scleractinia, also known as stony or reef-building corals, are the main builders of coral reefs. They have the ability to secrete calcium carbonate and form hard skeletons that are as hard as stone. This ability makes Scleractinia the primary building blocks of coral reef structures.
Reference(s):
cgtn.com
