yes. I'm going to say if he isn't eating and this is in fact columnaris, he may be to far gone. That's not to say you shouldn't treat him but the community tank should be your main focus now seeing as they've all been exposed.
Honestly it looks like duck lips from the images I have researched. He has not been eating for a few days and most people say its such a high mortality rate that even treating him there is a slim chance for survival. I will try to save him and be optimistic but not looking so good. I can see he lost some of his weight due to not eating already. Yeah I did a 100 gallon water change and I will do another in this week. I took off my heaters the temps are low and now I will be getting medications I will treat the whole tank.
My water quality is on point I did everything the same and never lost a fish in 8 years to any diseases.
I want to thank everyone who helped me and directed me in the right path. I will have an update hopefully he recovers fingers crossed. I know "duck lips' has high mortality even with treatment but I'm optimistic.


