I am in the process of setting up a 12 gallon nano and I am unsure as to which specific type of lights to get. I really like the shimmer effect that comes with metal halides so I am leaning towards them but nothing is certain. I do not want to have any limitations in regards to corals, clams, ect. caused by the lighting so im turning to you guys to give me your suggestions on watts and fixture. Give me your opinions!!!! ... Please 