Anyone ever heard of this or seen a DIY on something like this? I did some initial googling to see if anyone makes something similar, but no luck so far.

I'd like to mount DE mh bulbs w/reflectors on some kind of pulley or track that would allow them to be slowly moved across the top of the tank from side to side. Each light would only need to move aprox 18" over 8-10 hrs and would reset after each day's operation to the original position. This would seem to mimic the sun's progression across the sky and provide more even light distribution across your rockwork.

Does this sound like a good idea to anyone, or am I pulling monkeys out of my read-end? Any thoughts or suggestion are appreciated.