well the plants only have 6hours of dark that is when they use there reserver they only use so much. When they get bigger and i go to 12-12 i will put it up to 1200ppm. I measure the runoff with test kit. Take the water that runs out and put in tube and add drops and mach up color, it sthe only thing i have to test it so far.

So wait ur telling me i have too much light lol ? I know i should of used cfl's starting them but they just streched a little bit but they will catch up. I hope.:wtf: