Are these springtails and isopods?
It seems like they're both springtail species, as suggested by Arthur's comment.
The white one appears to be a type of folsomia, which is easy enough to guess from the appearance (mine don't jump though, I guess ruling out folsomia candida?).
You can compare it to this image of one, from Wikipedia:

I purchased a cheap USB microscope to inspect the second one further. Indeed, as Arthur suggested, it only has three sets of legs:

Additionally, I turned it around and got a look at the underside. I can only guess this is the furcula (though, interestingly, this one doesn't jump either!)?

I'm not sure what the genus is. Could be folsomia, or perhaps hypogastruridae? Either way, they're both springtails! Great news!