A heterotroph. Polyps (The actual living part of the coral. The hard rock like structure of coral is a by-product of the polyp's growth) within the coral use microscopic filaments drift in the water and catch phytoplankton that drifts past. This mainly occurs at night.
heterotroph
heterotroph
Heterotroph
Heterotroph.
heterotroph.
Heterotroph
Heterotroph.
heterotroph
heterotroph
Autotroph
autotroph
Autotroph