Based on images I've seen on the web, they might be root aphid larvae or thrip larvae. My setup is a dutch bucket system (fancy 4 gal hempy buckets) 50/50 coco perlite over 2" of hydrostones. I have a drain to recovery setup and I'm seeing bunches of these tiny beasties in the recovery tray while flushing fresh nutes through the buckets. This is very magnified ... the biggest of these is less than 1mm in length. They look like dust particles on/in the water. I'm dealing with some fungus gnats as well - the yellow stickies are showing less "traffic" and the diatomaceous earth will be here tomorrow ... so they're not my concern. Thanks in advance.