clf's to mh,here it goes,400mh is about 35,000-40,000 lumens and if u use 68w cfl's and each had 3500 lumens u would need 10 of them to get the lumens and now buy sockets reflectors ect..and now u are using 680watts of elec and there is now more heat from those bulbs than from one 400mh bulb.Now...