Hi all! I'm working on a project for a vet school, animating how gas flows through an anesthesia machine. I need to show the gas at the molecule level, like as lots and lots of tiny spheres.

So far, I've just been making big groups of spheres and manually keying them as they fly through parts of the machine. That's not working too well. I thought about particle effects, but they're always so hard to control, and I need specific actions. I read something about motion paths and flow paths... what are they? Would they help with all these spheres?

Thanks!