Hydro, Thrips, and nematodes

Okay, I feel like I have exhausted all of my resources and now I am turning to the great guys and gals of the rollitup gurus.
I have thrip issues that are not getting addressed with the sm90. I heard about nematodes and I wonder if it works on them as well as in hydo? Would they drown before they can help me out? I want them dead, gone, vamoose!

I had thrips not too long ago. I used pyrethrum once a week for three weeks and they were gone. It pretty much kills them right from the start but you need to follow up a few times to get those that hatch later.