I love to look at my tank at night so I fugured I'd get some moon lights. I never realized how bright those things are. When I turned it on last night, my zoas started to open up - I guess they were fooled into thinking it was day time. Is that bad for the corals? Do they require a darkness or "sleep" period? This is a little off topic, but will corals grow faster if you keep them lit 24 hours? Anyway, I ended up mounting the lights on one end of the tank so that it wouldn't shine directly down on anything too intensely.