Simply Koi and More Koi

Thankyou Duncan, That's put my mind at rest

One of my Koi has been gulping air and a couple of others seem alittle off. Only this one scape out of 5 did I find anything. It was taken from under the gill plate and I do not have a clue what it is.

Any help would be appreciated

https://www.youtube.com/watch?v=_sxX-UKTWU8