Coral Feeding

Corals can obtain food in several ways. The reef building corals mostly depend on the photosynthetic produce of the zooxanthellae for food. Corals capture zooplankton for food using two of their major methods to capture prey: the Nematocyst Adhesion and Mucus Entrapment. The nematocysts on the tentacles and mesentarial filament can be used to sting the prey and move it to the mouth. Some corals will use mucus and trap the pray and move towards the mouth. Pray size correlates to polyp size: small polyp = small food.

Most corals feed at night. This is because most zooplankton come out at night and are easy to capture. Most corals keep their tentacles in to avoid predators during the day, so they appear smooth at the surface, while at night they are furry with tentacles.

Prey can be directed towards the tentacles in many ways: Gravity may cause heavy particles to move towards the tentacles, direct impact is caused by water direction, inertial impaction is when the particles divert from the water flow and impact with the tentacles; after which the prey moves down the mouth, down the pharynx and to the gastrovascular cavity (gut) for digestion.