Looking at your pics, I would say the plants look a bit under watered, as the raised edges on the leaves are good indication of that (providing temps are ok). The #2 pic to me looks more like the start of a lack of Nitrogen or heat stress than overfeeding. I would also have moved the light closer to the plants providing you can keep temps in check, as your internode spacings seems a bit stretched out. If it was me I would continue with your veg nutes, increasing the dose a bit as they could be a bit darker green in color. I would not let them get much more then a foot tall as 6 plants in your tent will cause over crowding if you let them get much bigger. I like to use my MH bulb for the first 7-10 days of 12/12 then go to your HPS this will help the plants from stretching to much. I would also keep them on Veg nutes until the flowers begin forming, then start useing your bloom nutes, MJ needs a decent amount of Nitrogen while it goes through the stretching phase, if you cut back on the "N" to early your fan leaves will yellow and die well before they should. Other than those few issue they look great.
Good luck and enjoy the grow: Stlmatt
here are a couple of pic of my Sterling Haze(3) and Blackberry(1) these ladies are almost 4 weeks into flowering. I started the 12/12 when they were 12-14" tall and you can see I really dont have anymore room for more plants. They are in a 4'x4'x6.5' tent as well running a 600w light with a 150w CFL for some extra side lighting. Notice how green they are and no signs of any fan leaves yellowing or dieing off