first grow indoors my friend had a real gheto setup but plants were growing great.with only 1 4' flouresent balast with 2 2700 bulbs and one out door heat lamp for temp control plants were thriving i was very impressed good green color great growth in 4 wks plants are around 2.5 to 3feet however he went and got another set of 4 ft tubes @6500 lumens and 4 cfls and did away with heat lamp and the plants went from growing into the light daily(a 1" or 2) to nothing i am still in veg so i dont understand and roots also have plenty of space thanks