Cotton Mouth Progression

Hello members of fishlore,
Just need opinions on a few things about cotton mouth:
1. What does cotton mouth look like from onset to fish death?
2. How fast does cotton mouth progress in an infected fish?
3. How infectious is it if only 1 fish has it but is being housed in extremely clean waters?

The reason I'm asking this is because one of my newly bought bosemanI rainbowfish females has cotton mouth (in my opinion). There is a small spot on her bottom lip and a narrow band across her top lip. She arrived in this state about a week ago but the infection has not worsened and has not spread to any other fish in the tank. The water is extremely clean and the tank is modestly stocked.

Additional information:
I also took home the most colourful bosemanI rainbow male the store had available but was unaware that it was missing an eye. I cannot tell if this injury occurred recently or if he was born like that. Will he be more susceptible to cotton mouth disease with a wound like that?

 

Check this thread out. There is a ton of good info on Columnaris.

Columnaris Symptoms And Treatment | Freshwater Fish Disease 263058
As far as your wounded fish, he is probably stressed out which would make him more susceptible to infection/disease

 

Quarantine your new fish next time.

All you need is a 5 gallon bucket, cheap 50w adjustable heater and a cycled sponge filter from the main tank.

For now, I would suggest to do some frequent WC's at a minimum.

 

Sometimes rainbows look they have this but don’t cos they are quite skittish chasing each other and it’s just knocks

 

Quarantine your new fish next time.

All you need is a 5 gallon bucket, cheap 50w adjustable heater and a cycled sponge filter from the main tank.

For now, I would suggest to do some frequent WC's at a minimum.

Yes I have been doing water changes every other day as I don't want my prized rummynose school to get infected lol

Sometimes rainbows look they have this but don’t cos they are quite skittish chasing each other and it’s just knocks

Update: I think you could be correct. The white is still on her lips but the fluffy bits that used to hang off her lips are now gone. I'll keep up the water changes in the mean time.

Does anybody actually have any experience with cotton mouth though? I would like to know how high the risks are to my rummynoses? My water is extremely clean even before the water changes and now it can only be even more clean.