Corals and sea anemones are related to jellyfish. They live fixed to the seabed instead of swimming free. Sea anemones usually live as single animals in isolation, whilst most corals live in colonies - formed when new polyps bud off the initial founder. Hard corals build a limestone skeleton so that as nearby colonies expand and grow a reef is formed. Both corals and sea anemones catch their prey with stinging tentacles. Sea anemones are able to catch larger prey than corals can.

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