Sick Koi.

[bbensten]

Hello,

As we head into fall, the temps here are dropping into the low 30s. The pond water is still in the upper 50s. I came out this morning and saw 2 of my larger Koi floating (I thought dead) but they are actually alive, just unable to really swim and acting almost dead. Their gills are moving, and they are trying to gulp every once in a while at the top of the water. There are 4 other Koi that appear healthy at the moment. I am very new to Koi health issues so I have no idea what I am looking for but I have attached images so that hopefully someone can help me.

Thanks.

[RichToyBox]

As most issues are water related, we like to start with the numbers from tests for ammonia, nitrite, nitrate, pH, KH, Temperature of the pond. We also appreciate any information on actions of the koi immediately before this instance, like flashing, piping, isolation, breaching, etc.

It is not uncommon for koi to suffer from the cold and roll over and the cure, if that is the only problem is to raise their temperature, which generally means moving them inside, but if you do this, they will likely have to stay inside for the winter. You say you are from Virginia but that really doesn't tell me much. I live just outside of Richmond and I put a lean-to type structure over my ponds and covered them with 6 mil poly sheeting from Home Depot or Lowes, and was able to keep the temperature from falling much do to some solar gains, and lack of evaporative cooling. That may be all that is needed, but I would like to get the additional information for further treatments if necessary.

[bbensten]

Hi. Thanks for the quick response.

GH is 140ppm (mg/L)
KH is 20ppm (mg/L)
PH is 6.5
NO2 is 1ppm (mg/L)
NO3 is 160ppm (mg/L)

We are in Arlington VA. The Koi had been normal prior to this but had slowed down the amount they had been eating. The water temp is 48 as of writing this update. Thank you so much for the help.

[RichToyBox]

From the numbers on the tests, which did not include ammonia which I am going to guess is high based on the low pH and low KH. When the KH drops much lower than 100 ppm, the pH becomes unstable and can result in a pH crash. With the KH up for most of us, the pH will be solid at 8.3, but with low KH can drop even to the 5's. This pH shift will cause the beneficial filtration bacteria to die off, causing a rise in ammonia, and cause distress to the fish even before the ammonia rises. The high nitrates would indicate that there is a need for a large water change (50% or more with dechlor) before any other actions and then retest. I hope the tests were run with drop type test kits like API and not rely solely on dip strips which can be less the accurate. I would suggest adding baking soda, preferably late in the day, 1/2 cup/1000 gallons at a time until the KH is over 150 ppm for now. I would also add one pound of salt per 100 gallons to protect the fish from the nitrites, which should be zero or non-detectable.

The tap water should be warmer than the pond water which will help, it will most likely have a higher Kh which will help and it will have lower nitrites and nitrates.

Once the above is done, testing to assure ammonia is near zero, and nitrites come down may take weeks, but will need to be done to assure the water is safe for the fish. If the ammonia is high, I would get an Ammonia Alert Card from the local fish store to show the toxicity of the ammonia and treat with Safe, Prime, Cloram-X or similar dechlor products the bind ammonia (chloramine treatments).

[bbensten]

This is very helpful. I was thinking a partial water change but I didn’t want to add additional stress. To be clear, you are saying to attempt the water change with declor first, and if the numbers don’t stay stable, then try the salt/baking soda to make adjustments? Thanks for all of your help, I really appreciate it.

[RichToyBox]

Yes. Water change first with dechlor, then adjust KH with baking soda and add salt to protect from nitrites. After getting those done, then treat with the chloramine treatment to neutralize the ammonia.

[audioenvy]

Could be sleeping sickness. You would need to be able to warm the water or provide a heated sizeable QT for them. This disease is often accompanied by bacterial issues or parasites--but unless the water is warmed up there is not really a very effective treatment for either of those.