I do get involved with catching and documenting mites - more than I really want to, if the truth be known. But the result is that I am more familiar with them and know a little more about their natural history.
I also have some familarity with insects, and with biology in general, which helps when I see descriptions of situations described on this board. And I've been keeping animals for about half a century, and have seen or made many of the mistakes that people here are making. Again, this does not mean I'm an expert, but I do have some knowledge and experience.
OK. Now we can look specifically at your case. First, it's obvious that there's an environmental condition that allows this "pest population" to proliferate. Mites do not tend to bloom like this. Very likely you had Collembola, which would behave in exactly the manner you describe if your cage conditions were a bit too damp and there were decaying food left in there. They will not hurt your roaches, although I'm sure your roaches were annoyed to have these guys crawling all over them. (I would be too.)What I saw was tiny little dudes, smaller than grains of normal sand, congregating around the water and food (which were close together). I thought it was no big deal. Later I saw them en mass on a roach that had died. No big deal, I thought, they are just scavenging. Some time passed and they were all over in there, especially on the roaches. When it happened to my Blaberus roaches I could see them constantly scraping their eyes and face, which were covered in the same little organisms. ....
Collembola are very common animals, and if people on this board would take a little time to familiarize themselves with them, more than half the false alarms over mites would cease. It will vary in different parts of the country, but one place that I can always count on finding Collembola is in large flower pots or planters that have been kept damp. Water such a pot with enough water to flood it and Collembola will appear on the surface. Usually grey or white, and fast moving. They are scavengers on decaying material, especially plant material.
Again, I'm going to say "no". What you saw were almost certainly not mites. You had a Collembola population, and that would start exactly the way you describe. They are so common that you probably always have a few living in your roach colonies (I've always got them in my cricket colonies). And when conditions allow, they multiply rapidly.Do mites start out in the water and food dishes and later move to the roaches? Yes, for sure. I saw that in both cases.
I'll agree with you only half-way on this. Your experience would have done some good if you had recognized what the real problem was and reported it as such. But reporting it as a mite infestation and speculating on some unusual cause-and-effect perpetuated some of the superstitions that are already too abundant here. Sorry if I sound like I'm beating you up on this - I don't mean to dum on you or insult you. I'm really more interested in getting some more practical understandings out there.I think my experience is more useful to other hobbyists than your blanket statement that mites do not move from scavenging to clinging on our pets, that they can't hurt insects and spiders by entering booklungs (which I only suggested as a possible mechanism because I read it elsewhere),....
Also, my statement that these animals will not reach flood capacity and start moving into book lungs still stands.
OK. But it was coser to the mark than you may have realized. The "lice" or "mites" were actually Collembola.The lice thing, of course, was a typo.