Dude- I've found all kinds of living things in specifically roots soil-less hydro medium. mites, mealworms, fungus gnat larvae, even once I found a cut worm in my tray that I blame on roots. I seem to always have a fungii qnat prob no matter what when using that sh**. It's not bad for a coco medium but...worth it? I dunno. I have found that just leaving a mosquito dunk my hydro rez or soil feeding rez for a day, maybe fewo, can break the gnats "life cycle" (if I'm lucky). And the pantyhose over the top of the pots method is absolutely foolproof for gnats. (if your not to stoned to remember to put it on b4 the plants are 3 feet in diameter)