When I first started in saltwater many moons ago, my first tank had a snowflake eel, dwarf lion, picaso trigger and two domino damsels. The snowflake eel ended up eating one of the damsels but then left the other one alone when I fed it more. I was just feeding the tank and the trigger, damsel and lion would get all the food/fish first. It hardly ever came all the way out of its burrow when I fed it regularly by feeding all the fish and eel individually. My dwarf lion ended up eating the other damsel a couple months later.