I've been cooling my tank this summer with a clip-on fan blowing slightly at or below my MH pendant. I've been reading that MH bulbs need to be at about 100C - 180C to be efficient. What do you guys think? Do you guys have fans blowing at the bulb?
http://www.tridonicatco.com.au/produkt/BALLASTSHID.ASP
"Metal halide lamps are temperature sensitive and operate optimal at 100°C to 180°C ambient temperature and luminaires should be designed to provide suitable conditions"