6400 is better but 5000 will do just fine thats what i use Planetbulb.com look here
detroitfish Reviewed by detroitfish on . 5000K vs. 6400K Do these two color temps really make a difference for veg? It seems that at 1000bulbs.com some of their higher wattage cfls only go up to 5000K. Is it better to get the 6400K or is 5000K just fine? Rating: 5