Originally Posted by krap101
's put out alot more heat than normal tubes. The thing is, we don't *need* to do anything. Cooling on a computer is much more important than cooling a light, and cooling a metal halide is more important than cooling a t8. You may see an increase in life (by a little) but it's your choice.
In my case, the light bulbs may not produce alot of heat but the ballasts are like little ovens. And since they are crammed into a tight space (inside the fixture) they don't get very good cooling with stock fans.
It may not be necessary, but I think it helps with longevity.