I think the epoxy is a coincidence. My sps tank is full of epoxy and my clam is fine. I do know this, my tank that I house a clam in has 0 nitrates. I run phosban on this tank too and it does fine. I know from experience the liquid phosphate removers will kill a clam because they bond to the phosphates and these stay in the water. clams dine on this and it will kiill them.