I have a few fungus gnats... they're foodstock for my rove beetles and things always seem to balance over time... I see a flier occasionally, so I know they exist, but I only really see them when I'm actively watering my mulch... and barely any even then... coco is one of the components of my soil mix... but with absolute zero CEC, comparing soil to coco is kinda like comparing mice to elephants ... big ears, a tail, gray skin, and four legs... but still not even close... both can be great.. or terrible... but with coco, you're forced to feed the plant... in proper soil, you can allow it to have what it wants whenever it wants...