One of the most alien of all stony coral species belongs
to the genus Plerogyra. It is the 'Bubble Coral' (Plerogyra Sinuosa),
appropriately named for large translucent bubbles of salt water. These
corals are tolerant of a variety of lighting conditions, given ample time
to acclimate. Bubble corals have powerful stinging tentacles, so should
be kept ample distance from neighboring corals, and are most often kept
at lower levels of SPS dominated reef aquariums.