Strange Lumps On Koi?!

Hi, my koi and goldfish are becoming more active as the weather warms up so I went to feed them and noticed a lump on the dorsal fin of my biggest koi and a small lump on its back near its dorsal fin. I netted the koi to get a better look but have no idea what it is. I was hoping it was just fungus but it is hard and looks like something more serious.



I have no idea what do u guys think? Please help!

 

It kind of looks like scar tissue, as it is lumpy and hard. If the fish was injured there repeatedly, such as by scraping its dorsal on the ice (if you get ice) and it healed like that.

Doesn't look like a fungal infection nor a bacterial, if it were infected you'd think it to be red or pinkish.

 

Might be carp pox. Harmless. May or may not go away.

 

Is it contagious to my other fish?

 

Is it contagious to my other fish?

Maybe. I don't know enough to say. I think it's carp pox, but it doesn't mean it is. It's a possible cause you should at least look into and research, just don't take my word for it.

 

That is not carp pox, I agree with Demeter

 

It does resemble carp pox, I'm not sure you can just write that one off. Granted, I'm not the most experienced with diseases and infections, but the only other thing I know that causes lumps is fish lymphocytosis, and to me it doesn't exactly resemble that

 

Did a bit of reading and I can see how others are thinking it to be carp pox. It could be, in which case you can't do much about it. It's a virus, basically like warts, and they may go away on their own and yes it seems to be contagious. Keep the water quality pristine and stress low in the pond and hope for the best.