i'm not an expert on the lighting like your talking about, but the ballast is what fires your bulb, you will have to look at the ballast and see what it says, most times if you have a hps bulb, you will need another hps bulb for that hood. there are inter-changeable ballasts out there, but you have to do some research and find what you need for your closet, about 50w or greater per plant, but also keep in mind that the more the light the bigger the bud. My recommendation is go down to your hydro shop, look at the lights they have, most of the will be HID lights and those will give you the best results. I am running a 400w MH (somewhere in the 40k lums) for veg and when they go to the flower room i use a 1000w HPS (somewhere in the 140k lum's). This makes it very easy for me, one light for each room and they all came as a plug and play, no looking for an electrician or anything, plug the light into the remote ballast and then plug the ballast into the wall after the hood is hung....


hope that helps ya