[solchitlins]

After a recent tetra outbreak that I believed to be columnaris I treated my tank with kanaplex, a full course of 3 doses. Everyone is looking great except this corydoras that has had this spot on his nose. This isn't new, it's been there for months. It looks like someone erased his nose or it's been rubbed off. Anyone ever seen this before?

Video link:
https://m.facebook.com/story.php?story_fbid=1736733939905850&id=100007077826542

 

[Nordic]

I.d give him a methylene blue bath to see if it stains....

 

[WaterLife]

Could be mouth rot/cotton mouth disease (Columnaris).

I have seen severe barbel erosion, which is a bacterial infection (different strain of bacteria than Columnaris), that can continue to eat up the face.
If it was this, with healthy water quality, and a gentle med like Kordon Ich Attack/Rid Fungus, or simple Methylene Blue dips would cure the infection. Don't use Formalin/Formaldehyde meds on fish with open wounds or they have a good chance of dying.

If it really is Columnaris, the meds above wouldn't work. But you said you have treated with Kanamycin already, which is the med of choice when treating Columnaris.
Has there been any improvement or worsening of the infection seen the treatment? Make sure to keep the water extra clean since open wounds are vulnerable to infections.

Could you mention your water parameters (pH, KH, GH, TDS, temperature) as some meds effectiveness may vary based on water params.

 

[solchitlins]

My water parameters are middle or the road, 79 degrees and very clean.

How does the blue bath work? Catching her might be problematic. I could put her in a hospital tank but that would be stressful to be alone right?

 

[Nordic]

Just float a glass coffee jar or something in the tank, to heat it up. Double dose methylene blue, for 30 minutes.

More risky,would be a potassium permanganate bath (at half strength due to sensitive nature of cory), to seal the wound.

 

[WaterLife]

It would be stressful (dips are temporary, just 30 minutes or so -follow instructions-, multiple dips may be necessary), but sometimes you have no other options, and it may be necessary to do that, if there is not much else you can try to help her.

And yes, isolating social fish is stressful to the fish (sometimes it's necessary though if that sick fish is getting bullied or very out competed for food). When dealing with deadly contagious diseases, sometimes you have to put the safety of the others over the one fish, so quarantining can be wise to prevent others from getting harmed. For this case, I personally would just keep the sick cory with the others (still temporarily transporting it for dips) since you've mentioned this cory having this for many months and no others have developed symptoms.

"Good news" is, that Methylene Blue has also been reported to be effective against Columnaris. So for whatever potential bacterial infection the cory has, the Methylene Blue is likely to work. I would definitely use MB over Potassium Permanganate when there is an open wound involved.

Not exactly sure what "middle of the road" water parameters would translate to.
Has the infected site gotten worse/larger, or has it gotten better/smaller?

 

[Nordic]

I would definitely use MB over Potassium Permanganate when there is an open wound involved.

It is indicated for sealing off shallow wounds, but not for open red wounds. Get a milligram scale off ebay or from a headshop though if you choose to try this. Don't do the counting crystals thing.


It is one of the most useful substances in an aquarists kit, provided you know what you do with it.
Multiple MB baths would be my first route though, it is also well absorbed internally.

 

[solchitlins]

I noticed the nose about 6 months ago. Figured he rubbed it raw by accident. I have noticed no change in it before or after treating the tank with kanaplex.

Ph 7.2, kh 120, gh 130, nitrite 0, nitrate 20, temp 79

Is this what I want to order? Methylene Blue?

I also have polyguard on my shelf.

 

[WaterLife]

Yeah, that's the right Metyhlene Blue.

I'm not too familiar with Polyguard, but I see it has some Sulfa and Nitro in the ingredients (antibiotics). If the rest of the fish are doing fine, I would not use is (Polyguard). Just stick with the Methylene Blue for now.

 

[Cheetah2]

For lower stress QT treatments, I've hung 'plastic baggers' (the large transparent plastic ones that pet stores use) on the inside of the tank. That way they are still in their familiar tank, but separated from sharing water. Adding a plastic floating plant gives some cover.

 

[solchitlins]

Update. I went to the lfs and got the M Blue med, I also bought aquarium salt because the owner said he would try that first, or also try that.

How much salt is reccomended safe for planted tanks with cory cats? I know it's less than normal, right?