Changes in zooplankton densities and composition, combined with changes in water clarity, which affects the potential for photosynthesis, are fundamental factors that affect coral growth and reproduction. Water flow enhances zooplankton capture overall, although some categories of zooplankton prey have relatively successfully escape behaviors - and can avoid capture. It turns out that many corals are food and flow limited, and could be growing faster than they are. Some corals do not depend on prey capture to meet the majority of their energy requirements. Instead, photosynthesis by their symbiotic algae is more important.
Sediment can be a food source for corals, as well as a stressor.
Generally, sediment is thought to stress corals because extra energy is required to remove sediment when it settles on live tissues. However, some coral species are very good at sorting through fine sediments that fall on their surfaces, and they can pick out the most nutritious particles. Interesting facts about corals Coral tentacles are armed with tiny, poisonous stinging cells, called nematocysts. The nematocysts discharge into potentail prey upon contact and help to imobilize and hold prey until transfer into the coral mouth. The nematocyst types and abundances differ amoung coral species.