i had a rbta move right onto the shell of my crocea, i thought for sure they were toast, but they lived that way for weeks before i finally had to break them up. no appearant damage to either. good luck!
Yes, The RBTA will sting the mantle of the clam. One of my clams has marks or scaring from being stung. Of course this is not an overnight result since it is an ongoing battle (the clam never wins) for well over a year.
I also have a smaller RBTA mounted on the side of the clam. Surprisingly this one does not give him as much trouble because when they are both open the RBTA stands above and straight out from the clam and the clam does not get stung.
The seem to coexits well enough but the marks on the mantle make the clam and I both sad.
Both are hard to move. The clam is probably rooted by his bysis threads and you do not want to tear those if you attempt to move it. In a critical situation clip the threads as far away from the clam as possible. Also it can be very hard to peel the anenome off of the rock. A current directed at the RBTA is supposed to make him want to search out a new spot.
I'd try and get the BTA to move away. They will walk over anything they feel like and take no prisoners. I had mine kill a nice piece of pocilliopora last week while I was gone. It had happened so fast that my friend taking care of the tank had no idea it had happened. When I got home it was a completely clean, white skeleton. I'm sure it quickly RTN'd, and am glad it didn't get anything else. I had been given the piece as a frag and it had been growing nicely. If that BTA ever got close to my crocea, it would be no contest, the anemone has got to move!
Thanks so much for the reply's. I looked this morning and seen that the clam has moved about 1" from it's original mount, but is still attached. I have two RBTA' (1 split ), and the other is to close for comfort to an acro colony. Tomorrow the powerhead comes out, and the persuasion begins.