I would think the sebae would have to be very large and all anemones pose the risk of eating fish but from what I am aware of it is usually carpets that end up eating fish but I imagine your sebae could be doing it if big enough and or the fish are small enough. I am helping a friend with his new 180 and his clowns and goby pair are fine but every time we add new fish they end up dieing, wrasse's, jaw fish and lawnmower blennie and myself and a few others are going crazy trying to figure it out so all I can say is good luck. I have never heard of aps killing fish but I guess anything is possible