Identify this and how to treat?

[Carpe et diem]

Hi all and a big thanks in advance for any help and advice you can give...

So, I have this thing that has developed on the side of one of my Koi. Please view the attachments for pictures.
The best I can describe it is that it's about the size of a 20p piece (maybe a little bigger) and is like a raised half circle that appears to be filled with clear liquid and is quite squishy to the touch. It really gives me the urge just to burst the bubble but I know that's not the right thing to do.

You will note that there is a small black bit in what appears to be the middle, but it is a bit hazy and unclear to see exactly what this is, but as you can see from the pics, the fish does naturally have a few small black specks on her colouration so this black spot in the middle may just be completely natural and one of the black colour spots. I honestly don't think its a parasite but hey, I'm not an expert here. Just looks like a normal black part of the fish.

It doesn't appear to be causing any distress to the fish and the fish isn't flicking or behaving in any abnormal way which is good.

Can anyone help identify this and ultimately know how to treat it?

Again, thanks in advance and I can provide further if needed.

[Alburglar]

Unless anyone else has a better idea, I'd say it's Probably carp pox. If so, there's nothing you can do about it, but it will probably go away when the temperature warms up.

[rolo]

i have three koi that got it when they were taken out of the temp pond into the new pond in late December two were minor and have cleared up the third was far worse but is far better its getting there. all three had it around the fins especially the tail looks like lumps of jelly.

keith

[Djstiles999]

Doesn’t look like carp pox to me, that said it’s not something where I’d say I know what it is,

[Carpe et diem]

Thanks for your replies, very much appreciated 😊