Tridacna clams do not need supplemental feeding with sufficient lighting. It's really quite shocking, but they are able to synthesize pretty much everything they need. The small amount of protein they need is easily extracted from the water. If you feed any corals or filter feeders, there is almost guaranteed to be enough matter in the water for the clam.
A coral waves little sticky bits around to catch food. Clams actively pull and expel water and are therefore much more efficient feeders.
The maxima clams do need rather high light so try to get him higher once he is acclimated.
That is one of the truest blues I've ever seen in a clam. Fantastic deal! At that price, I'd almost be suspicious! Score!!!
Someone stop me! Please! But... not just yet...
55 Gal Tropical FW
55 Gal Mixed Reef