It's starting to get a little cool at nights here, and with Tennessee weather being what it is, I worry about it actually dropping a little too low and day now.

I have some cattleyas that I'm going to be moving inside within the next couple of weeks. I was looking into getting some lighting for them since I don't have a southern window. I was looking into getting a new lighting setup, but since I can barely afford to even pay my phone bill right now, that's out of the question. BUT, I do have an "old" (old as in I've had it for a while, but new in that I've never used it) lighting setup for a reef tank I was building. It's two 175w MH bulbs, reflectors and ballast. The bulbs are 12K (12000K). I was wonder if this would be good enough to keep the orchids inside during the fall/winter/early spring?

The spot I was looking at is about 2.5ft tall so the lights would be hung from there and the plants would be @ 1.5ft away from the bulb... is that too close? I've been trying to read around but I can't really find much information on MH bulbs and orchids.

Any help would be much appreciated.