Tridacna derasa - The Derasa clam is one of the easiest clam species to care for. In the wild they reside along the sand beds adjacent to reefs. These clams require adequate lighting and nutrients in the aquarium to grow and thrive. They can even reach sizes of 2 feet! They are a great reef safe sessile invertebrate that is sure to be the center piece in many aquariums. Approx ~3" - 3.5"