Conversion bulbs end up being more expensive than just buying another light for veg.
You'd be way better of just getting separate lights like some cfl's or flouro's. It doesn't take much for veg at all.
i am new to growing and in which order would you use the lights? can you us them at the same time? for my grow space, which will be tiny, i was thinking one 250 watt HPS and a couple CFL's on the sides. let me know what you think!