(WPF)

The biologically processed matter in this biofilm has formed a thick soup. I'm seeing a lot of very small protists mixing with medium-sized ones. This is on top of the water in the jar where floating biofilm is most dense, like a sticky layer. An interesting thing is that the densest material is also the lightest. It floats on top of the water surface. Layers of organisms move about under the surface.

https://youtu.be/m4N8-bmcv8Y