In hydro,
I just spray the roots off with H20 and back in to the rez.
Do that a couple of times a day until they are gone or not a problem.
The yellow sticky fly traps are very good as well.
I catch predators all the time and toss them into my grow areas, garden spiders, lady bugs, tree frogs, geckos, lizards, etc..
They all do a pretty good job.
PS one of the spiders grew to be about the size of a US silver dollar. I had to toss her out, as she would scare the shit out of me by running over my foot.