Jim,
It's common knowledge that you plan to upgrade the fish AI to reflect each species individual habits and personalities which also includes an eel that would come out of it's coral hiding place at night when the lights go down. On that note, how about the other species at night? Have you considered giving them more timid or aggressive AI based on the change in lighting? Perhaps some species could do the opposite of the eel and go into hiding to avoid him? Or did you already mention that in some obscure post elsewhere on the forum that I might have missed?