Clam death.

[asylumdown]

I suppose I should have caveated that statement. To my untrained eyes it looks like I have two different species of bristle worm in my tank. I even triggered a mass spawning of them cleaning the tank last weekend (not sure what I did but holy crap was it impressive). There's dozens of other species of 'bristle worm', so what might be true for the kinds in my tank might not be true of another species someone might have brought home on their rocks. Maybe there's a kind that likes to munch clams and I've just been lucky so far.