Unhappy Comet

[SLStormin]

Hello. I’ve got a 350-ish gallon outdoor pond with 10 or so assorted Comets & a couple Koi. Generally everyone came through winter ok, with the exception of this guy.
We’ve had this pond for close to 20 years and have had fish age out & expire, which is what I thought was happening with this poor guy. However, he/she has been lying nearly motionless for several weeks now, only moving slightly from time to time. If touched or disturbed it will swim around a bit, only to quickly come to rest again. It can remain in the same spot for days.
Any thoughts on what could be going on?
Thanks in advance

 

[Andy Sager]

The fish looks a bit emaciated so there is that but I see an area just short of midway down the body that appears to be missing scales so it's highly possible the fish was attacked either by the other fish in the pond or maybe a bird or small animal. I don't give it much hope but if you can place the fish in a separate hospital tank to protect the fish from outside invaders, that would be the only thing I see as having the most opportunity to have positive outcome but again, I don't give it much hope.

Hope this helps.