I don't remember exactly but I know it was bright and white. Stay away from anything that will cast a yellow tint. Also I thought that CFL bulbs did not seem to have enough oomph to light my light box properly. Maybe the ones I had were not high enough wattage though.
I agree with Chewbecca about flash being much easier on the geckos' eyes than continuous lights. Plus you can catch them with their pupils open rather than closed down to tiny slits.
Thanks for the compliment! Your shots are great as well.
I have a D40 which does not feature Nikon CLS so rather than using my pop-up flash to trigger the SB600 I'm using a set of cheap radio triggers. I'm familiar with how CLS works but I don't have much experience using it so I'm not sure how you would go about dimming the command flash. Actually, I always figured the flash was dim enough that it wouldn't affect the overall lighting.
I got one of the flourescent daylight energy saver bulbs. What I do to save the eyes is put them in with the light off. Once they get into position then I turn the light on. When I build my bigger one maybe I will look into the transmitter to make it easier on the albino eyes.
Wow, you know way more about flash lighting than I do!
And, yeah, the pop up flash can/does cause issues.
You can still get red eye and harsh enough shadows if you don't work it well with your SB600.
At least it does this for me.