Call me old fashioned, but, I've decided to include some metal halides in my new systems. There will be two (along with some other lighting) over the new 6' x 4' x 2' high tank. The area above this tank will be enclosed on the front and sides (with sliding panels), but open in the back - this area will be 30" high. This will actually be my first time using metal halides inside an enclosure (all of my metal halides have been open air before), and I'm thinking I'm going to want some air circulation in that space to move heat out a bit better. I can get inexpensive fans, say, at Menards, and BRS sells a clip-on fan, but I worry about long term safety with such fans when run continuously - it seems such fans sort of wear out quickly. Can anyone suggest some sort of fan to blow air into this space (from the rear) that would be simple to set up and that would be a bit higher quality and long lasting? Or... maybe I just should get some sort of inexpensive clip on fan and plan to replace it yearly?