I told Dave, I looked at it under a microscope and it appears to be predominantly yeast. Right size and morphology, some were budding. There was some debris that made it hard to tell what else might be in there, and anyway, a little bit of bacteria can have a large impact on the beer, which can make them hard to find under a microscope if they're not isolated.
So I've plated it to some yeast growth media, but bacteria might grow on it depending on the strain. I'm growing it kind of cool, around 20C instead of 30C. It was growing the fridge though, so that should be fine. I also plated it to one with an antibiotic that will kill any bacteria but not affect the yeast, so I'll have a purified strain(s?) to play with.
I still need to grab some LB plates to plate it to, I only had ones with antibiotic available. That will favor bacteria, since there is no sugar for the yeast to grow.