15tube = 15watt CFL. All a CFL is the tube you have wraped around and around. So they are the same. But i have something similar check out my log

My ghetto CFL groe box. WITH PICS!

i thnk thats it
TheBudReaper Reviewed by TheBudReaper on . Closet grow question My brother is starting 3 clones in his closet lined with mylar, under a 15watt warm fluorescent, with 50/50 perlite/potting soil, as well as MG bloom fertilizer. No humidity dome, fan, etc. We would like to know if this will be an adequate set up for a first time grower? Rating: 5