I just bought a new Koi and Comet for my pond. It's well-established with good readings (a little on the soft side, however.) I put them in and watched a while. The Koi is fine, but after a day, the Comet (Momo) is acting strange.

Momo is leaning to one side, all fins lowered and tucked in, not really moving or eating, and sort of floating in one spot at a middle depth. I put him in the pond on Tuesday and pulled him Friday for a hospital tank. I don't know if there's a swim bladder issue or what, so I quarantined him and dosed him with Clout.

In the hospital tank, I noticed all fins are out and up, he's active and eating (and pooping). I did notice he has a black mark on his left gill area about 1/4 of an inch in diameter. He's red and white and this is the only black spot I see on him.

He's been in the Clout tank for about 36 hours now. Should I reintroduce him, keep him separated longer, etc.? He still swims a bit funny (a bit sideways at times.) Thanks for the help, Chris

Hi Chris and welcome to the site.

The black mark concerns me. It could be a signal the water is a bit off. Can you give us all the information asked above? This is essential to us helping you.

Laurie:

I tested the pond water the other day and it was all in the safe range (a bit on the soft side, however.) I had a fish shop also test it and they confirmed it as well as stating the ammonia was very low. We don't usually feed our fish (there were four, but one is "missing", so I added two a week ago) and they have always been healthy.

The pond is oblong, about five feet wide, five feet long and three feet deep. The largest fish is about ten inches while three others are about four inches long. Everyone else is feeding fine. As I said, he was perky in the hospital tank (eating and pooping very well), so today I put him back in the pond.

Again, he started acting funny; hiding out, not really swimming around or eating. And, I noticed he seems to like hanging out under the bubbles and stronger current of the water pouring in from the waterfall (this one is like a stream from a faucet on full). He was hanging in the "rough water" of the hospital tank filter too.

I'm hoping maybe it's the stress of in and out over the past several days. Any thoughts?

Well, thankfully Momo's acting much better today. His fins are up, he's swimming better, he's eating the flakes at the top of the water was well as diving for the ones that settle, he's hanging around the other fish, etc. I think he's going to be ok.

He still tips to one side sometimes, but I think he's just swimming that way around his favorite hangout (the waterfall). He's acting so much better!!! I will keep my eyes on the black spot on his gill cover. From what I've read, it may be that color as whatever it was heals.

I am glad to hear he is doing better. But again we need you to post actual numbers of the tests you perform. I am concerned about "any" ammonia being in the pond. For it to be up to functioning right there shouldn't be any ammonia reading, not just a low one.
Post those numbers and we can go from there.