plant stunting and root problems

[Bobo Bolinsky]

A new one, a handful of plants not thriving, and I did see very small (about 3 mm long) skinny very fast moving bugs in the soil and rootballs of plants, both sick and apparently not visibly sick. Bugs are too small/fast for pics. Not root aphids(scoped for quite a while) not springtails, don't see any fliers so likely not fungus gnats and I really don't know if they are to blame for browning roots and poor leaf development. Doesn't seem like any slime on roots. I cannot find these fast crawler things anywhere on line!
Pics:






Earlier tried testing azamax on these small pots but the bugs came back plus too $$$ for wider use in my room
I wanted to test long lasting Bayer Advanced Fruit and Citrus and Veg insect control on some small containers which these root pics are from, but I can not find mixing or this per gal., only per sq foot. Anybody know how much to add per gal. The Imidacloprid active ingredient is weak compared to say Merit 52 so how ever that would affect the proportion don't know Anyone know this?
ideas and help much appreciated!
BOBO

 

[Midnight Tokar]

I'm pretty sure the dosage rate for Bayer Complete is 1 Tablespoon per gallon of water. I wouldn't use that unless you knew for sure what you're killing and had at least 60 days left...........
I'm thinking Root Aphids but that is way too big for them.

 

[Bobo Bolinsky]

Got 60 days, was going to test on just a few small pots so, I'll check on the T/gal thing and hopefully do it tomorrow, thanks