Blue corals are hermatypic corals, and therefore 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 (4). In return, the coral provides the zooxanthellae with protection, and access to sunlight.
Blue corals reproduce sexually by brooding. Instead of releasing eggs and sperm into the water where the fertilised egg develops into larvae, like many corals do, the larvae of blue corals develop inside the polyps. Each polyp produces one or two larvae, which subsequently attach themselves onto the colony before release. This may allow the larvae to develop further, and thus when the mature larvae are released into the water column it is able to settle in quickly. This means that the larvae will settle in a habitat that is already proven to be suitable for adult growth and reproduction. The larvae of blue coral have not been observed to swim, and thus dispersal of this coral is determined by water movement (6).