Sea anemones usually attach themselves to solid obejcts on the sea floor, rocks or corals. However, they can glide around very slowly and tend to live for a long time.

Corals such as reef-building corals are generall found at depths of less than forty metres, where sunlight can penetrate. Sunlight is necessary for them to grow. Other corals can be found in all depths of the sea, from shallow to depths of more than 5 thousand metres.

Jellyfish are found in all oceans of the world and some even live in fresh water areas such as lakes. Some jellyfish live in sheltered harbour-type habitats and other inhabit the deeper depths of the oceans. Jellyfish can frequently be seen by night, bobbing around in the water.