400w Purple Kush x Sour Diesel, Blackberry Bubba Kush, Black Domina grow

Hi everyone! I've been lurking this board for awhile and have finally decided to join your cozy little online community. I am in the pursuit of knowledge relating to all things cannabis and plan to learn all I can from people who are more experienced than myself. So, to get the ball rollin' here are some pics of my new babies. The first one is Purple Kush X Sour Diesel, second is Black Domina, and third Blackberry Bubba Kush. Two have been in coca coir for 9 days so far and still haven't rooted. The Blackberry Bubba Kush was taken as a cutting from a plant 4 days ago and is just sitting in water until I get my bubble cloner up and running. I'm not using a humidity dome, and currently they are sitting under a 250w MH. The very tips of the leaves are starting to turn yellow so I made some shade for them, I think the 250 is too much for my little girls! I'm using a weak solution of Pure Blend Pro (Grow) and House and Garden Multi-enzyme. Oh, and I didn't use any rooting hormone due to budget restraints. How long will it take for these things to root? Am I doing something wrong? I mean, the plants look healthy, but still no roots, can I do anything to encourage root growth?

Oh and here is the space I will be growing in (see pics). It's 4 feet wide by 2 feet deep by six feet tall. There are two 4" heavy duty computer fans (one blowing air in, the other blowing it out) to keep things nice and fresh. I plan to add two more fans when I induce flowering, but for now, this works surprisingly well. As you can see I have an air cooled hood for my 250w MH. This will be connected sometime today hopefully. A buddy is letting me borrow a 6" centrifuge fan to exhaust hot air from the light out of the cabinet, and then out of the room. The 6" is a bit of a problem because my ducting is only 4" and all my cut holes are 4" as well but I know how to take care of it with a simple adapter piece. I plan on going either DWC or Aeroponic, but I want to know if my nutrients are suitable for these methods. Does anyone know if Pure Blend Pro can be used as a stand alone nutrient in these hydro methods? I have heard all kinds of stuff about organic nutes not being detectable on a TDS meter, insufficeint mineral supply to the plants, and so on. I would like to get this cleared up ASAP as I plan on constructing my hydro system tomorrow so any advice you guys might have would be greatly appreciated, seriously. I can't afford to buy new nutes, these were left over from my last soil grow. I have done DWC before, but never using PBP. So basically, I have to construct a system around these nutes, my limited space, at least three plants, and very little cash.