Clam is 1-2″ when fully open!
Tridacna maxima has the widest distribution of any Tridacnid species. It is found from the Red Sea, throughout the Indo-Pacific region, to Australia and Polynesia. It usually occurs in shallow, clear water, high current areas where they are known to form high-density populations. They will attach to the substrate with threads from the byssal organ.
Maxima clams have many different colors and patterns. For this reason they are usually graded for sale in the aquarium industry. ORA grades include Ultra, Ultra Gold, Purple First, Green First and Gold mantle colors.
They require high light levels in the aquarium and are best placed high in the tank, close to the lights. They prefer rocky substrate to attach to. The reflection of colors will change as one views the mantle from different angles.