Fungus Gnats and Thrips

Currently the grow is in 1 gallon fabric pots
3.5 weeks into veg
Soil medium

So I got bit real bad by a bag of Big Rootz soil. Stuff is garbage, literally. Found bits of plastic in the soil. I didn't notice any bugs when I was potting up my plants from their original solo cup, but then noticed some gnats around the plants a week or so later. I've been going the sticky card route and sprayed with Neem oil on 4/20 and again 4/27.

I noticed some leaf damage and a film on the leaves that resembled slug slime residue. While inspecting the plants on 4/27, I noticed what I think is a thrip that scurried into a nook on a fan leaf before I could get it on tape.

My plants need to get potted up into larger pots. I am running as fast as I can from that rip off Big Rootz trash. Should I wait until I've eradicated the fungus gnats and thrips before changing to the new medium (stonington blend that's been in quarantine tote)? I plan to get some Captain Jacks spinosad spray today. I sprayed the plants with Neem Oil 3 days ago. Can I hit them with the Spinosad tonight?

I really want to get rid of these fuckers and get these plants into bigger pots ASAP. Any help insight would be appreciated!

Just look at this douchebag...

Doused the plants with Captain Jack's dead bug. Hopefully that will knock back the thrips.

Definitely saw less gnats today compared to Wed. Tonight, I'm going to vacuum out the top layer of soil, water my plants, then replace with food grade DE. Will see how that does and transplant into the 3 gallon pots with Stonington mid-week if the bugs are in check.

Found one thrip during my inspection last night, so hopefully another round of dead bug will do the trick. Removed the top inch of soil and put down the DE. Will leave for a few days until the next watering.

I think I'll try the acv/sugar/dish soap method to catch any adults. I didn't see any on the yellow sticky cards, but saw some gnats flying around the plants during inspection.

Hey man, hope this finds you well,
I had a lot of fungus gnats in my pots about a month ago, one of my pots had like 200 flying fungus gnats everytime I watered it, and now, today that same pot is fungus gnat free. What worked for me is l bought some nematodes, called Metarhizium anisopliae, and I bought some BTi, Bacillus Thuringiensis. And ive been spraying Tuesdays with BTi and Fridays with neematodes, sundays I spray neem. In a week my problem of fungus gnats had gone down immensely, 2 weeks now, its practically gone.

I havent bought spinosad, maybe it works, but I advice you to get a second remedy like nematodes, and alternate.

Thanks @DoobieDoobs! I was thinking of getting some nematodes next if this round of DE and medium removal doesn't work. My real issue is the thrips, which the spinosad is for. I'll probably start feeding silica as well, to bulk up the leaf structure and make it harder for these fuckers to feed.

Best thing I found for Thrips, aside from sprays, are Minute Pirate Bugs. I actually enjoyed watching the little bugs work too. After that run I took the tent down and cleaned it thoroughly.

I haven't found a thrip or fungus gnat since Monday. I'll change the medium tomorrow when I pot up the plants.