I'd be a little concerned putting a clam in a redsea max with the stock 2x55w power compacts of a Red Sea, expecially a maxima or crocea. A deresa or a squamosa would probably do ok under that lighting scenario with the deresa being the best choice and you can usually find them for around $25.
Remember also, clams will suck up the calcium as well so make sure that you are dosing everyday. At the size you will get it, 1"-2", they also need plenty of food with a small micron size, such as phytoplankton, roti-feast or oyster-feast. Lastly, if the tank hasn't been setup for at least 6 months, I'd wait.
I know I'm putting a damper on your desires, but, I'd rather see you be successful than "try" to keep a clam under minimal conditions and fail.