Hi there, I just got a massive 12" maxima and introduced it into my tank. It looks amazing and seems quite happy. However, my yellow clown goby loves to use it as a sofa. I see it sitting on the clam's mantle every so often. It doesn't seem to bother the clam much but it does retract when the fish moves. Should I worry about it and what should I do if it's a problem? Thanks for your help!