I don't have a reef tank (just argonite substrate some fake plants and a few cuttlefish - s. officinalis in the tank) and there has never been a live rock placed in the tank in question, although it is possible that there might have been cross contamination from another tank I have that does contain live rock. I have had damsel fish in there on and off over the past couple years but only when there are not active cuttles in there and there have been no other animals. The anemone I pulled out today is small clear and my best guess is that is is aiptasia. I have read that aiptasia have been known to hurt small invertebrate species. My question is, does anyone have experience with cuttlefish or other ceph interaction with anemones such as this and should I be worried about this becoming a serious issue. Also, is there anything else that this might be, or be indicative of, in my tank? Thanks for anyone who can help me out here.