UPDATE:
The clam looks better, he's more open and his holes, whatever you call them....... are more open and closer to how they looked when I got him. I think he's on the road to recovery!
The nudibranch has gotten off of the calm and I have subsequently learned that he can't hurt the clam. The blenny has been sold, and replaced with a royal gramma (which I just discovered last night before bed has ich grrrr), and the real shocker is the pygmey, get this.
So I begin to mess around hooking up my new MH ballast and putting the new bulb in the socket. I take a look at my sump to just to see what is going on down there and low and behold who do I see down there Blink my Pygmey Angel!! I couldn't believe it! He found a small area of my over flow that was not covered by the screen and swam down into my sump from it. Boy he doesn't know how lucky he didn't end of in my gravity fed protein skimmer bc that would have been the end for him! My display drain goes 2 places, the sump and my skimmer. Anyway I'm going to hook up a light on a timer down there and give him a week to see how the clam does. I also added some PVC for him to dart around in.
Pictures of the calm will come soon