Ok I have a dual 400w pfo ballast (m59) and have been using xm 20k bulbs for a little while now. I love the colors I get out of the bulbs but I cant get that great of growth. I heard to use radiums but the ballast I have does not over drive them so they wouldn't work like for some people. I thought about helios, evc, blv, etc. I'm asking for suggestions on what bulb would give me good color still and good growth.


