For many years I've used an inexpensive trick to greatly diminish the spread of mites to other cultures or enclosures. I use 100% natural diatomaceous earth. Diatomaceous earth is a very fine white powder that dries out the exoskeleton of insects that travel through it causing them to dry up and not survive.
I began using diatomaceous earth around my fruit fly cultures that I use for feeding my dart frogs. I put some newspaper or packing paper on the shelf, and I put a dusting of the diatomaceous earth powder down on the paper, and then I place my fruit fly cultures directly on top of the diatomaceous earth. This prevents any mites from traveling to other cultures.
I use a very similar method with my springtail cultures with the exception that I build a little "barrier wall" of the powder around the springtail cultures. It greatly limits the spread of mites and other springtails into the other cultures. I choose this method of the barrier wall around the containers because I'm opening and closing the containers to feed the springtails and I want to minimize getting any diatomaceous earth inside the culture. With fruit fly cultures, I'm not adding food to feed the fruit flies, so if there's some of the powder on my hands, it isn't a problem.
Diatomaceous earth can also be used around bioactive enclosures to limit mites and escaped fruit flies. For example, if you have dart frogs, which you are feeding fruit flies, there's always a few flies that run wild and escape. The diatomaceous earth barrier will help prevent the flies from wandering around your home.
Just as a word of caution, diatomaceous earth is a fine powder, and even though it is 100% natural, take precautions and wear a breathing mask when spreading the powder. I do use my hands to spread the powder around, but I always wash my hands immediately after.