Hey guys, just joined up and randomly saw this post! Have noticed the balls of water rolling and exploding while honing on my jnats quite commonly. I believe it has to do with silica content in the stones and it becoming hydrophobic! This should explain it pretty well https://youtu.be/oUzDkKKcjaY

As for the light!? I can't say I've noticed that yet. I'll test my honing in the dark skills soon..