I painted the inside of the canopy with Tremclad high heat white paint tonight and, I gotta say, WOW. I tried the canopy with just 2 4 foot power glo's and was blown away. INFINITELY brighter, and a much whiter light.
The VHO's are still giving off a yellow hue, but not too bad now at all. I think I will replace one of the 3 bulbs with a higher K bulb, but I wont need to do them all.
Thank you all for the suggestions, you saved me a lot of money in experimentation.