I've done something similar using self-ballasted 175w Mercury Vapor bulbs for uv enhancement. They did seem to frost up nicely. Unfortunately the bulbs didn't last long and put out some serious heat. Got'em off Ebay 4 for $35 or so, if I recall correctly. Ended up using 10000k CFLs near the end with good results but not as pronounced as the MV bulbs. Probably not enough wattage. A 250MH might be the way to go. From what I'm learning now I think a couple halogens for the last few days can help to ripen your trics too.