That 1st clam, its mantle isn't always folded up like that, is it?
Also, are those Acans in the last picture? I have the same ones... love the color contrast on them.
The clam recently turned itself sideway in the current. When the vortech gets rippin full speed sometimes the clam folds over.
The last pic is actually a prism favia that cant make up its mind whether it like my tank or not. I do however have and acan with the same color scheme but can never get a pic that brings out its true colors. The purple is so dark.