Cotton Mouth?

[ChrisXL]

3/4 of my zebra danios have little white lumps at the tip of their mouth (bottom lip). Their behavior is normal, and they are all active and seem happy. 2/4 of the Danios have had the white lump for at least 2 months, so I'm pretty sure it can't be cotton mouth. None of my other fish have any problem.

Any idea what this could be, and might it not even be a problem?

 

[minxfishy]

What are your water stats and did you cycle the tank with these fish? White cotton like fungus around this mouth is usually a bacteria infection/mouth fungus, especially if its spreading to the other fish. Any chance of a picture? If it is mouth fungus/columnaris, you will need medication, in the UK the tried and tested meds are pimafix and myxazin (used together).

 

[ChrisXL]

All water stats are spot on. The tank was cycled with these fish. If it is cottonmouth, I just don't understand how they are living. They've had it for months. Will get a pic when I can.