If you have other cfls in the same room you can still add this light blue is used for veg but has long has you have daylight tubes[white]it will be fine the more light that you add is better then less the other lights will counter balance the coulour spectrem.find out if it's a warm or cool if it kicks a little heat out then have this a little higher than your cool tubes this will aid in giveing the plants a little warmth but either way get them has near has possible to the plants inces off the tops.you want the lights near on touching the plants this will stop leggy plants,leggy plants mean less bud less bud is no good.flouresents of any kind can be great to get the plants going if used right you want nice close internodes.good luck dude.