Giant Coral Tubes are a Coral species found in the Safe Shallows, Crash Zone and Kelp Forest biomes. It does not currently do anything other than provide the player with Common Coral Samples when hit with a knife. Giant Coral Tubes are a good source of Calcium Carbonate. If hit enough times, the Giant Coral Tube will disappear. Giant Coral Tubes can be large enough for a player to swim through them, as well as small fish. Certain flora also inhabit coral tubes, such as Veined Nettles and Acid Mushrooms.