Tubipora musica, Organ-pipe coral, above and below is found in shallow, sheltered waters of the Indo-Pacific. The hard skeleton of calcium carbonate has many pipe-like tubes giving it its common name. In life each tube contains an 8-tentacles polyp, which are active during the day. The skeleton is red, but is obscured by the green or grey polyps. Colonies can be up to 1 metre across. Unfortunately this coral is widely collected for the jewellery trade.
Above is the Elephant skin coral, Pachyseris speciosa. It is found in the Indo-Pacific, and is widespread and common throughout its range. It tends to be located on the lowers parts of the reef, from 4 - 46 m deep. Its plate-like form allows for better light capture enabling it to survive at these depths.
It is fished for the aquarium trade, and when alive it is pale brown to grey, paler around the edges making it a very attractive specimen. A colony usually measures 10-20.
Above and below is Mushroom coral, Fungia sp. It is found in the Indo-Pacific. Unusually for a coral it is free living, so does not attach to reefs, and it has the biggest polyps of any coral. It can grow as large as 30 cm in diameter, and when alive is often brightly coloured, pink, red, purple and blue which makes it popular with the aquarium trade.
Related pages, main Cnidaria page - main Anthozoa page - corals 2, 1.