Return to the Ponds in the UK Forum | Post a Follow-Up

Mystifying Koi behaviour

Posted by JohnTW16 SW London (My Page) on
Sun, Jun 5, 05 at 5:58

Over the past 48 hours two of my koi have been exhibiting quite odd behaviour. I noticed in the pond on Friday that 2 of the koi have separated themselves from the rest of the group. I thought they were both ill. One was lying on its side, the other on its belly, both at the bottom of the pond both together. 6 hours later they were up an about looking normal and feeding with the rest. This morning they are on the bottom again one on its side, the other on its belly basically looking as though they are about to expire. Againthey stay very close together as though they have "paired off" However, when I try to capture them, they scoot off only to sink back to the bottom again. Has anyone any idea as to what might be happening? The rest of the pond inhabitants seem fine. The nitrite problem I posted a few weeks ago seems to slowly returning to normal. The goldfish in the pond are currently breeding like there was no tomorrow. I am mystified as to what might be happening and would appreciate any suggestions

Are my koi trying to breed and are just exhausted?????


Follow-Up Postings:

RE: Mystifying Koi behaviour

Sounds like they are sick. Are they clamping their fins to their sides when lying on the bottom? Have you seen then flashing/rubbing recently? Any marks or wounds on them?

RE: Mystifying Koi behaviour

  • Posted by AJC_1 8 the fens (My Page) on
    Sun, Jun 5, 05 at 9:31

It sounds like Nitrite poisoning, Nitrite can kill quickly in a week fish but in strong healthy fish it can take a few weeks.

Try and get a close look at thier skin, see if you can see little red viens anywhere, or reddish patches if so catch the fish and dump both in a tub of water with 1 ounce of salt per gallon and leave for 30 minutes, salt is a good alrounder but it also can counter the effects of Nitrite poisioning, it might not cure the fish, depends on how much damage is done, but it might buy them time to recover a bit, but full recovery if possible will take a while, you will need to repeat the salt dump in 5 days until they look ok or die :(

Dont leave the fish alone in the salt water, use an air pump and stone if you have one, if not you might need two tubs, so if a fish shows signs of floundering take it out and pop it in the fresh water for a bit, then pop them back into the salt.

RE: Mystifying Koi behaviour

I have used cooking salt for all treatments and I know that we are told not to use table salt at all, yet my mother-in-law says that she always used ordinary salt for her tropical fish. Is it really very bad to use ordinary salt because all her fish survived as far as I am aware.

RE: Mystifying Koi behaviour- nitrite update

Thanks for the comments everybody. Only the dorsal fin is clamped to the body. I have tried to catch them, but with no success so far. They just scoot away as though nothing is wrong. I checked them this morning and although lethargic, are still alive. I carrried out a major water change yesterday night after AJC's comments and hope this will help. I have also stopped feeding them. Hopefully another water change on Tuesday will see a reduction in nitrite levels. I was also going to ask the question that Alison has posted. I have no pond salt at the moment. Will "Saxa" do in the short term?
Will nitrite poisoning cause permanent damage to the fish gills or can they completely recover?

This has been a real learning curve for me. After following "advice" and cleaning the pond in May and getting a giant nitrite spike, I have learned to choose my time more carefully. Also I assumed that as the level of nitrite went down the effect on the fish would decrease. Therefore I did not do enough water changes, preferring to let the pond do it naturally! I think this is now wrong. If anyone else has a nitrite problem, then do whatever is necessary as quickly as possible to reduce it to zero. I only hope that in going through this learning experience I will not lose any fish.

Yours worryingly
John TW16

RE: Mystifying Koi behaviour

  • Posted by AJC_1 8 the fens (My Page) on
    Mon, Jun 6, 05 at 8:36

First off everyone makes mistakes and has to learn, often the hard way, so dont feel to bad.

Salt, you need cooking salt or aquatic salt, never use table salt, it contains other addatives that can cause problems by itself.

do a water test every two days until the nitrite level goes out of view , then test it twice more 4 days appart, then set a once a month test unless you see strange behaviour of your fish.

Nitrite affects the blood, some call it affect brown blood, because thats what it does send the fishes blood brown, hence the redish viens or rashes on the skin, but if its only a minor dose in a fish, a high salt bath can reduce the affect of it, giving the fish time to recover, but it will have some affect on the koi that is permenant, it might not live a full life, but a bad dose from high levels over a long period is fatal, and it might take a while to kill the fish off too, not a pleasent one, thats why its important to monitor nitrite levels often.

To my mind the test kits with the drops are the better ones, the tablet test are ok as long as the tabs are fresh, they are less accurate with time, so a minor reading can be higher than you think, they cost more to buy but cost less than all your fish!

RE: Mystifying Koi behaviour

  • Posted by donusa Syracuse, NY (My Page) on
    Mon, Jun 2, 08 at 12:21

I have 2 koi that are acting strange. one is lying on the bottom of the pond and when I come near he pops up and swims as normal and feeds. I took him out of the pond and gave him a salt bath treated him with fungicide and ICH. I noticed that he is also loosing scales. I checked the water and everything is fine execpt the PH is high so I oput in low ph. This fish is no longer lying on his side but sits in one sopt in the tank where I am treating him, rather listless. Any suggestions?

RE: Mystifying Koi behaviour

Pardon my ignorance, but can someone please tell me how you get nitrite problems? I only have goldfish, frogs and a newt in a 9' x 8' pond with no filter or pump and everything seems so healthy! You are scaring me!
Big Kid

RE: Mystifying Koi behaviour

As I understand it (but I may be wrong):
You have fish- alot of fish.
You feed your fish because there isn't enough natural food in the pobnd.
Your pond gets cloudy and smelly because of fish poo and also waste food.

You then have to get a filter to clean the water, and you may need waterfall or other way to oxygenate the water because there isn't enough oxygen in the water for the number of fish etc etc. But if you love ornamental fish and koi (which don't have a very good digestive system) you don't mind.

But that's why I have wildlife ponds- I don't feed apart from an occasional bag of daphnia for the newts and newt babies. And I have lots of plants to provide oxygen and to support alot of food for the newts (and sticklebacks in one pond).

RE: Mystifying Koi behaviour

I did wonder if it's to do with decaying food matter. Like you, I originally wanted just a wildlife pond but I was persuaded to adopt some goldfish and they live happily with the other wildlife. I never feed anything and they all manage to find enough grub in there.

Oxygenator-wise, I notice the Hornwort starts growing a lot at this time of year and I don't thin it out till I've bought replacement Elodea Crispa which seems to either disappear or gets eaten over the winter months. I have loads of water hoglice and I know they eat detritus. I wonder if they clear up fish poo, as well as decaying plant matter? My dodgy murky water in spring has now cleared by itself so, again, no need to panic because I know it's just 'cycling' and will soon right itself. I still think the secret is barley straw and the right oxygenators.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Ponds in the UK Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here