i have a 55 gallon and i have a 165w hanging over the tank which is dimmable i have noticed that when the blue lights are on they look great, but when the other lighs come on the corals are not as pretty.. i do not have the lights on full they are on less than half.. they are hung about 12 inches above the water should i leave them where they are or bring them up... the manufacture recomends 12 to 16 above the water.