Biology

The distinctive red pipes contain the coral polyps which, like many other corals, have microscopic algae (zooxanthellae) living within their tissues. Through photosynthesis, these symbiotic algae produce energy-rich molecules that the coral polyps can use as nutrition (2). In return, the coral provides the algae with protection and access to sunlight. In addition, organ pipe corals can capture plankton and organic particles from the water using their feathery tentacles (6).