Start by making a green water culture so they have food. They are filter feeders and only get food by filtering water for fine particulates. Ground up fish food isnt even fine enough.
To be fair, you don't hear of many people keeping these successfully.Thanks for the vote of confidence!
Did you do any research on clams before you decided to keep them? I would consider myself an advanced aquarist, and even I dont think I have a tank that would sustain them and I have very mature tanks.what is a green water culture?