go to home depot to the light bulb section, they have grow tubes there, they will say something to the effect of grow light, but you can buy any 6500K bulb, for veg.
Yeah i already veg my plants and now i want to flower to them,can i use that same bulb or is there a different bulb i can use for flowering that comes in a 4' tube light.....thxs
the warm white, or soft white bulbs... usually around 2700k... its a redder bulb that is better for flowering... i'm assuming you have cool tubes in there now..