Sodium Light Question?

I just switched to 12/12 and changed from a Halide bulb to Sodium. It seems like it runs cooler than the Halide. Can I run it closer to my plants than the Halide bulb without the threat of burning them?

I wouldn't recommend it, a few inches is close enough. What wattage are the MH & HPS bulbs?

They are both 1000's; same convertible ballast. The HPS has some time on it so I'm wondering if it could be worn out?

I've never used MH, only HPS & CFL, so don't know for sure. If you can put your hand on the top of the plant without burning your self, it's probably ok for your plant.
HPS bulbs can last 20,000 hours + but for optimal efficiency changing once a year is a good idea.

Reiss is right with the hand trick. A stationary 1000w can be 10-18" away. With my mover and cool tubes I can get 3-4" away. I usually try to stay abut 12" though. WM