When did your mites start showing?
I first noticed my mites when I started adding corrugated cardboard to my bin, which had been set up primarily of coconut coir and some handfuls of shredded newspaper.
I'm wondering if there's any relation here between the decomposition of the cardboard to fueling a growing mite population. Of course, it's possible I only noticed them at this time, but I have to say they're very easy to see. At the time I added my corrugated cardboard, there was a brief mold explosion on the top of my bin as well, and I know that some mites do feed on mold, so that would make sense. Has anyone else had similar experiences?
Since this happened, I've stopped using cardboard (despite how much everyone says worms love it). Honestly, mine don't seem to mind just having lots of their coir to move around in moved with food scraps. My worm population is beginning to explode with tons of baby worms present through all parts of the bin.