So, just as I was about to do the parasite med, I noticed something had changed. Now it looks almost like the thing burrowed into him or maybe it's fungus from a physical wound. There's no redness around it. And he doesn't seem to be bothered. No flashing. He's eating and swimming well and schooling with the others. I'm not sure what it is anymore. Under the microscope, I don't see it moving at all...it doesn't look alive.
Everyone in the tank seems healthy and I've been keeping a close eye on them.
This pic isnt' great but it gives you an idea.