Care for Clams/Coral on my live rock?

I may have been doomed by the LFS here. They sent me home with a very cool chunk of live rock (even after informing them I had a 2 month old tank) that has some sort of large clams attached to it that are very much alive and even coral (I think some sort of polyps) growing all over it.



After much research I feel my tank is probably not nearly mature enough for these.



Do I need to add anything extra to my tank to atleast give these a fighting chance?



-Thanks