I just turned 12/12 yesterday with the addition of co2. The plant is almost to 20 inches. Thats about 8 inches in 7 days. I've also added a pair of florescent grow lights to the sides. I noticed the light wasn't getting down to the bottom of the plant. If its going to grow 2 or 3 times its current size, that is going to be a problem. The extra lights raised my temps too hot, so I also put in some custom cooling. I also took my clone cuttings, hopefully its female. After this plant is done, I am starting fresh with the clones. I have designed a new room that is going to be much more efficient than the box. My biggest problem is noise, the fan is just too damn loud. Ive got a much better fan, much cooler lighting for my clone mothers, and I am switching to 18/6. I just want to keep the new moms happy, and pumping out copies.