Do you have any sources on this? I only ask because if you try to research this behavior the studies I have found done by Marine Biologists do not see this as being an inherently negative response. It has been documented that even otherwise healthy corals do it when they wish to absorb organic matter that is outside of the coral body as well as capture zooplanketon and other food with these kinds of nematocysts and mucus nets. I have been unable to find any scientific study that indicates this behavior is ONLY a negative response and that filaments are only a defense mechanism in reponse to stress or irritants. While it CAN be in response to an adverse condition such as severe starvation etc, it's not the only reason.Never meant to start a debate. Wether you agree or disagree. Filaments stringing out of your coral is not a sign of "happiness" or a "hungry" coral. The corals may do this in a response to foods being added to the tank, but it shouldn't be looked at as a "positive" feeding response. They are being irritated by all the fleshy food and food particles floating around. Filaments are a corals defense mechanism. They come out when threatened, stressed, or irritated. Same thing will happen if you're cleaning anything in the tank, glass, rocks, removing corals etc.. Think about it for that matter of time food is present in the tank the corals are surrounded by miniaturized fish chum.. not a very healthy or happy environment for the corals. Never said it indicates the coral is unhealthy, its just not happy at that time.