I want to use moon light in my mbuna tank. I tried the super bright blue led and found that they are too "directional" the light hardly spread. It looks like theatre projecters on 1 actor on the stage or more like a Pink Floyd concert.I would like the light to be spread evenly accros the tank. I thought of using a blacklite tube but I'm not sure of the effect on the fish. I dont want my fish to "glow in the dark" I just want to observe night life. Any suggestion?