The first thing I would do is give them a very light feeding with high nitrogen (a maximum of 0.5 EC or 250 PPM), just so the plant has some nitrogen available in liquid form. Especially when it goes into flowering it and is expanding/growing it's flowers, it needs more nitrogen. Nitrogen is the growth nutrient.Here are side pics of the three plants in the tent.
The first two pics shows one of the leaves turning yellower in only a couple days from when I first posted pics. NOTE: The fan in the pics has been turned off for several days after someone here on ICMag told me to turn it off.
Pyrethrum works wondersNever mind
This is the best advice you'll get here.That's a lot of work with your soil. Not sure there are any real benefits going that route. Next crop I would try a more simple approach. Buy a bail of promix and be done. All you do is water it and get great results. I've tried organic this and that over the years but always end up going back to the basics. Remember it is just a weed. Less is more sometimes. Each to their own.