White bump on lip - Columnaris?

I've currently got 3 glowlight danios in quarantine, had them for 2.5 weeks and about 3 days after purchase I noticed 2 of them had white upper lips, and one of the white lipped ones also had a white lump on its lower lip (this one was hiding and not eating initially).

The white lump initially looked kind of fluffy or frayed (like a thick thread hanging off) but now just looks like a smooth bump.

I suspected columnaris because of the fluffy appearance and started acriflavine and methylene blue treatment (I'm in Europe so I can't really get hold of antibiotics or furan). The treatment finished a few days ago but the fish look the same (except that the fluffiness of the white lump disappeared).

All 3 are now eating and seem quite active and swim together but they are very skittish in the QT as it's quite bare. They are quite stressed in there.

If it's not columnaris or a contagious disease I'd like to add them to my planted 25 Gallon tank so they feel a bit happier and are less stressed but I obviously don't want to introduce disease to my other fish.

I've attached photos of the fish with the white bump on its lip, sorry for the poor quality, it's really hard to get clear pictures of them as they either move too fast or hide in the moss.
Sorry, forgot to add that after the acriflavine treatment failed, I added 1 teaspoon per gallon of salt to the QT and there's still no change in symptoms.

The salt (or maybe the acriflavine) did mess up the beneficial bacteria though and I'm now getting 0.05 nitrites in the tank. There's 0 ammonia, and the pH is 7. I'm doing daily 50% water changes to keep nitrites down and I use prime as a dechlorinator.

Any ideas of next steps/ treatments to try? Or maybe this isn't even columnaris?

 

It's probably a bacteral infection, Mouth Rot. It's good the Danios are eating, that's a significant indicator that they likely will survive the infection.
Unfortunately any mouth tissue contacted by the bacteria will be destroyed & will not regenerate. It often results in an ugly gaping hole mouth, but the fish usually are capable of eating.
It's been my experience that Mouth Rot isn't readily contagious, but it would be a good idea to quarantine the Danios until the infection is over.

 

It's probably a bacteral infection, Mouth Rot. It's good the Danios are eating, that's a significant indicator that they likely will survive the infection.
Unfortunately any mouth tissue contacted by the bacteria will be destroyed & will not regenerate. It often results in an ugly gaping hole mouth, but the fish usually are capable of eating.
It's been my experience that Mouth Rot isn't readily contagious, but it would be a good idea to quarantine the Danios until the infection is over.

Thanks for the input. I thought mouth rot was the same thing as columnaris? Is there a different bacteria responsible for mouth rot?

I'm feeding them garlic infused flakes to try to boost their immune system. Hopefully that along with the salt will help. Poor fish, I hope they don't lose parts of their mouths

 

I've had fish survive mouth rot. Although missing various amounts of mouth tissue, they were still able to eat & lived fairly normal lives.

 

Update:

The salt appears to be helping. The mouth rot or columnaris or whatever it is hasn't got any worse and looks a bit better today? The whiteness of the lips has reduced and the white bump on the one fish is smaller.

I'm worried about the nitrites though. I'm away for a week in 2 days and there won't be anyone knowledgeable available to do water changes on the tank. The fish are too small to go a whole week without food, so I have an automatic feeder set to give them very small portions every 2 days (in order to try to keep nitrites from exploding).

I think I will also lower the salt level from 1.5 teaspoon per gallon to around 1 teaspoon per gallon over the next 2 days, and move some media from the main tank to this tank (hopefully the main tank isn't where the infection originally came from...).

Hopefully that's enough to keep nitrites down and keep the fish alive until I get back =/

 

A while back i had a tin foil barb that had that, I treated him whit metafix and some salt, he didn't eat for over a week, then he started eating little more after about 2 weeks or so he started swimming more and eating more and was doing much better. I put him back in my 65 gal and he was doing fine. He did have some damage to his mouth, and it was harder for him to eat from the top so he would eat from the side but other than that he lived a normal life and was ok.
i wouldn't worry about nitrates for week IMO it should be fine it may take some time for the fish to heal but if they are eating that's a good thing.

 

When I had this on the past the thing that worked the best was a formalin dip. Sorry that Europe has banned all the good chemicals. I would also recommend sulfa antibiotics since they don't kill benefits bacteria.

 

Well to Update:

I came back from vacation and all 3 fish seem to be fine. The white lump has shrunk on the one fish, it's almost completely gone (maybe it's just scarring that's left?). They all look healthy, I fed them and they all ate. I think they're recovered / recovering.

The tank had 0 nitrites when I got back, but after feeding the fish it went back up to 0.05 which is annoying, I guess the cycle bacteria still haven't bounced back from the salt/ meds. Maybe it doesn't matter since its only a QT, I can just keep up with every other day water changes until quarantine is over.

So now I'm wondering when I can add these fish to my display tank with the other fish? Should I keep them in observation for another week to see if symptoms reoccur, and if not, acclimate them over? Or is 2 - 3 weeks better?

 

I would say if you wanted to wait another week it wouldn't hurt, but since all the fish are eating swimming and don't have any signs of anything i think it would be ok to add them in another few days or so and keep a close check to just to make sure they are in a good condition.