Yea the little ones were doing good at 600 ppm before, the only reason I got the MH was for the Veg since ill be doing flower at the same time, that is if the clones work out and all. I tend to read allot and dive in deep....first grow with aeroponics. Do they look the right size for 3 weeks from seed, I read somewhere that they should be 1-2ft by now. I was using that MV lamp though, they probably would be the right size if I just used the HPS to start.