The species in this group, which comprises several families, present a ramified,
fan-like form and can grow to a height of 2 m. Their skeletons can be used for decorative
purposes. These animals prefer a fairly dark environment, where they live attached
to a support. They sometimes have a tendency to be colonized by other organisms,
such as sponges or filamentous algae. Their food must be very fine and distributed
daily. Size: 15 cm.