Suggestions for treating issue on Otocynclus

[FJB]

I purchased a small group of common Ottos (O. affinis?) to add to my tanks. They have been in quarantine for a week, and my common practice is to keep them in here for at least a month.
However, today I noticed something in one of them, which probably was there all along but I had missed. It looks like an injury just past the dorsal fin, which appears to have developed a secondary fungal infection. The fish acts normal, only its fins are not as open as the others (not happy?), but swims around fine. I know the photos are fuzzy but I could not get any better. Photos are all the same fish, the only one affected. However, if you recognize what it is, and can make suggestions, I would be grateful.
I have treated with salt only at this time and are maintaining excellent water quality in a fully cycled tank. Many thanks!!

 

[fishorama]

I'm not sure what it is (columnaris? the "slow" version) for both white area & clamped fins. I would probably go with both a gram negative & gram postive antibiotic very soon rather than later. I don't think salt is the answer, it doesn't treat bacterial infections & may just stress the otos. Maybe erythromycin, or Maracin 1 & 2 together.

It's always good to QT (kudos!) & your ill fish looks nicely filled in, not skinny. Don't wait, & treat all the new otos, they've all been exposed to whatever it is.

 

[NoodleCats]

I agree with fishorama, columnaris and needing some antibiotics asap.

 

[FJB]

Thank you guys. I will get the the antibacterial today!
Cheers to you.