plants dying after using nematodes

Hi, Im currently running an air atomized aeroponic system. On the last run I had a massive fungus gnat infestation in my root chamber that attacked the plants in week 4 of flower and never went away no matter what I tried. So this run I took a preventative approach and hit the root chamber with pyrethrins and neem at the first sign of gnats. A week later there were still some gnats living so I researched a more natural solution and found nematodes. I picked up a 5,000 count sponge from my local hydro store and mixed it in 2 gallons of water. I was told that you cant over do it with these so I figured Id used the whole sponge on my two 4x8 chambers and a mother planted in soil. Up until then the plants were looking healthy as ever and growing beautifully. 2-3 days after adding the nematodes much to my surprise I find all of my plants, including a mother plant, which is in soil and a separate room, dead or dying. The leaves are crisp and wilted like they dried out under the sun. The ONLY thing that was changed was the addition of these little bastard nematodes. Is there anyway they could have killed my plants?! And if so, what can I do about it? Im so upset and discouraged to have come this far (week 3 flower) to be losing this once so promising crop.

As I just posted this im thinking. I did not pH adjust the tap water that I mixed the sponge with. This run at about 7, whereas the nuts I use are 6-6.3. I wonder if this could have had such a drastic impact as I sprayed them directly and entirely over all surface area within the chamber. FML. But if that were the case it seems like it wouldnt have taken 2-3 days before killing the plants. also the way they are dried up and wilted it looks like a lack of water somehow but there is no issue with the sprayer.. plus the mother plant in soil was effected even worse. its also worth mentioning that the roots in the chamber physically still look fine.. Im freaking out and have no idea what to do but watch them die.