Facultative corallivores are defined as organisms that regularly consume coral without it comprising a large percentage of their diet.

It is thought that some facultative corallivores, such as some damselfish, eat coral to promote algal growth. Many facultative corallivores also graze on algae, which competes with coral for space and resources. By grazing coral, it may provide better conditions for algal growth. Aggressive grazing may keep the algal community in a state