Just finished installing a 70W fishneedit metal halide, with the stock 20K bulb over my 5.5g. Corals are still getting used to the new light. The stock 20K bulb looks more like a 14K, but is still fairly nice and is VERY bright! Temp hasnt been an issue yet. I moved my fan a few inches closer and everything seems ok. Hoping to get a few new SPS corals in there now. Transferred my chaeto from the DT into my first chamber for a cleaner look.
It took me a few days to figure out how to install the light, as the supplied arms that clamp onto the side of the tank are pretty much useless. Soldered up some 3/4 copper tube and drilled it into the back of my dresser mirror! Needless to say, the wife was not too happy about that part! Overall, I am very happy with this new light and do not have any complaints thus far.
Video:
YouTube - 5.5 Gallon Pico Reef