A very beautiful and commonly-available mollusc. Unlike marine clams such as T. maxima and T. derasa, this is a scallop and it is a nonphotosynthetic filter-feeder. I feed my tank liquid phytoplankton every few days.
When it feels endangered, it will squirt out water to quickly scoot to another part of the tank, so don't expect that where you place it in the tank is where it will end up; it goes where it pleases. It needs lots of live rock crevices to be happy and protected; my first one was too bothered by the animals around it and ended up dying early on in my 55gal Tank; fortunately,
I've had much better luck with the second one, which has found a place under the pagoda coral and has been thriving in the 60gal Tank, though it can usually only be seen from the side of the tank.