Please help! my koi are dyeing

[Marcelo B]

Good morning everyone, hope this message find you well. I need some advice / help, yesterday I had a terrific event happened. I saw one of my koi swimming strange, kind of spinning while swimming, others were swimming face down, others swimming and heating the rocks and walls, some of them would stay up on the surface kind of gasping for air, swimming slow or not moving that I could touch them (no jumping). These symptoms where happening to each of them sparely, like every hour or two I would see one, then it started happening faster.

Then when I realized, I started taking them out one by one in to a separate tank and I put some medicine in it (Tetra Pond water treatment) . Some of the ones I transferred were pretty much dead, not moving, just dead, and within one or two hours they started to get better and this morning still fine, some of them where not as bad when I transferred them, and they did not make it, one of them, an Oscar, had extremely bulge, but as of this morning, he was still alive and less bulge. (this might had occurred while I added some salt in to the tank as I was freaking out)

Attached are some pictures of them, you will see that some are missing flakes, must of them did not show any visible physical symptoms, only one of them show some redness and still alive for now.

These fish had been on that tank for months and they were pretty healthy and active.

Things I know:

- Last Tuesday I added a string algae removal product, but after about 12 hours I regretted and I did a 30% water change, aside of turning on the constant water supply.
- I have two ponds (one 1000 gallons and one 200 gallons), I did the same treatment on the small pond, and nothing happen to those fish in the small pond.
- In the 1000 gallons tank, I have a fountain on one end and a waterfall on the other end, I also have 6 oxygen rocks at all times and 6 more turn on at dusk, so I should have plenty of aeration. The small pond shares the same air pumps.
- The water temperature is bout 80 to 82 (during the hot time of the day)
- I have a constant well water supply running at all times to keep the water temperatura down (without it, the water would get as high as 102 degrees and keep a constant temperature of 92-93 degrees at night (I measure the dissolved oxygen under these conditions once and it was 92% at night), I have this same well water supply from the same well and pump in the small pond as well, and those fish are perfectly fine, and they are babies.
- On the 1000 gallon tank I have a bio-filter and a 80 Watt UV Light.

Attached are some pictures to get a better idea of the set up I have.

Any advice is greatly appreciated.

Thanks

Marcelo B!

 

[Meyer Jordan]

These are all symptoms of Ammonia toxicity. Test your pond water ASAP.
Your Oxygen level is probably OK, but if you want to take an accurate reading, testing should be done early in the morning when the Oxygen level will be at its lowest.
In which pond were these affected fish?
And where are you located? Are those air or water temperatures?

 

[Marcelo B]

Thank you very much for your repose, I tested the ammonia and it showed fine. I'm located in Miami Florida, the affected fish where located in the large pond., and those numbers are the water temperatures.
Also, I would think that if the ammonia level in the water was high, I would think that it will have also affected the small koi in the small pond since they share the same well water supply, and those are fine, please correct me if I'm wrong.
What could cause a fast increase on the ammonia level?

Thanks

 

[Meyer Jordan]

Thank you very much for your repose, I tested the ammonia and it showed fine. I'm located in Miami Florida, the affected fish where located in the large pond., and those numbers are the water temperatures.
Also, I would think that if the ammonia level in the water was high, I would think that it will have also affected the small koi in the small pond since they share the same well water supply, and those are fine, please correct me if I'm wrong.
What could cause a fast increase on the ammonia level?

Thanks

I am trying to assess your situation by making sure that all if the important facts are indeed accurate.

The problem may be in the well water. Many wells along the Florida East Coast are suffering from increasing intrusion of salt water. I had a client in West Palm Beach who was also on well water. The salinity levels were high enough top be toxic to most fresh water fish. They switched to municipal water and the problem was solved.
So testing the salinity of the well water should be a top priority. Also the chemical and mineral content of well water can change quite quickly depending on the aquifer.
Your fish are exhibiting signs of very severe stress.
What is the actual numeric reading for the Ammonia as it becomes increasingly more toxic are water temperatures and/or pH levels rise?

 

[Faebinder]

Bet your ammonia levels are high. Essentially sounds like you killed enough algae to lose your ammonia buffer for the pond. Algae consumes your ammonia. It will take a while for the algae to come back. You're gonna need 90% water changes every 3 days for two weeks. If you also lost the beneficial bacteria in the filter, the nitrites may spike later. To be safe go get an ammonia and a nitrite test and check daily. If you spike, do a water change.

 

[Marcelo B]

Hi, I just tested all the waters I have in my property (well, large pond, small pond, pool and tab (I tested the pool and the tab water to see if the results were different to make sure the testing material was accurate, and it did)

Well water:
Salinity: 360ppm
Ammonia: If not zero, maybe 0.10ppm (its a color chart so it could be tricky)
NO2 and NO3: 0

Large pond / where the deaths happened:
Salinity: 350ppm
Ammonia: 0
NO2 and NO3: 0

Small pond:
Salinity: 370ppm
Ammonia: 0
NO2 and NO3: 0

Pool:
Salinity: 4500ppm - I just did tis one to make sure the device was working fine
Ammonia: Not tested
NO2 and NO3: Not tested

Tab water:
Salinity: 155ppm
Ammonia: 1.0
NO2 and NO3: 0

Attached there is a few pictures of the ammonia and salinity test.

Jordan, do you service the Miami area? if not, do you know anyone?

Faebinder, the algae treatment product was only for one night (when it requires 3 to 4 days), the next morning I did a water change of 30-40% and then I have the constant fresh water supply running, which its constantly refreshing the water to keep it cool on both ponds.


Let me know your thought

Thank you both !!!

 

[Meyer Jordan]

Jordan, do you service the Miami area? if not, do you know anyone?

Sorry, but I am retired.
I do not personally know any of the contractors in the Miami area, but Google "Koi Ponds, Miami" and you will get a list of quite a few contractors.

Do the fish show any physical signs- sores, red streaking. white spots etc.

 

[Marcelo B]

Out of the ten that die only one of them showed missing flakes, the other nine show no physical signs, they were just swimming facing down, or spinning while swimming or up on the surface kind of gasping for air, others would stay at the bottom.... then from the onces that did not die but at some point showed the same behavior, one has some red on the fins and tail (Koi), another one has bulge eyes (this last its an Oscar, not a Koi), then the other 2 Oscars and 3 Koi, do not show any physical signs and they are still alive in a tank with some medicine.

 

[Mmathis]

So, how many TOTAL fish do you (or DID) have in the 1000 gal pond? And about what size are they? That sounds like too many fish, if there were 10 dead ones....and 9 survivors....? That means you have, like 20+ koi + The Oscars....but I might have misinterpreted the numbers.

And do I understand that you have Oscars in with your koi....?

It does sound like ammonia level might have been too high, even though your readings don't back that up. Are you using a liquid (drops) test kit or strips, and do you know how old the kit is? What is the pH?

And no, water in 2 separate ponds, even when it comes from the same source, won't necessarily have the same readings.

Hang in there!

 

[Meyer Jordan]

You stated that the water temperature would easily top 100F without the contant input of well water. This begs the question-How much sun radiation does this pond receive daily in hours? From the photo it seems that there is not any plant cover.

 

[Marcelo B]

Hi Mmathis, thank you for your replay, I had in total before the incident 14 Koi with an average size of 5-6" and 3 Oscars about 6". Now I only have 4 koi and the 3 oscars left.
Yes, the Oscars are with the Koi.
I used liquid drops to test the ammonia and the kit is about 6 months old. The Ph level reading came back at 7.0 - 7.3.

Hi Mayer, it is correct, without the reticulating water, the water temperature could get up to 100 degrees during this time of the year. There is not much plant cover outside the pond. But out of the 32 feet that it measures, the first 10 fit are cover with a porch cover type of roof that gives it shade (on the deep end), then it has a bridge where the fish can get under and there are also 4 plants inside the pond.

Thank you both!

 

[Mmathis]

Hi Mmathis, thank you for your replay, I had in total before the incident 14 Koi with an average size of 5-6" and 3 Oscars about 6". Now I only have 4 koi and the 3 oscars left.
Yes, the Oscars are with the Koi.
I used liquid drops to test the ammonia and the kit is about 6 months old. The Ph level reading came back at 7.0 - 7.3.

Hi Mayer, it is correct, without the reticulating water, the water temperature could get up to 100 degrees during this time of the year. There is not much plant cover outside the pond. But out of the 32 feet that it measures, the first 10 fit are cover with a porch cover type of roof that gives it shade (on the deep end), then it has a bridge where the fish can get under and there are also 4 plants inside the pond.

Thank you both!

How deep is it?

 

[Usman]

i think ur oxygen level has fluctuated at certain time either night or at day under heat , usually when we treat algae at once from artificial ways it kills it suddenly and it sucks all the oxygen from water it can happen after some time too day or 2 when it starts decomposing effecting pond echosys & fish immune sys, it might have fluctuated badly at some time then came back to normal ,

warmer the water, the less dissolved oxygen it can hold. When a dense bloom produces a surplus of oxygen on a summer afternoon, the oxygen will not stay in solution and escapes into the atmosphere
​

. if there was prob or amonia or salinity etc in water then these fishes which are left wud have shown signs too . in ur case smaller ones shud have survived or lucky ones

This type of oxygen depletion may kill some fish directly or cause sufficient stress to weaken their immune systems. Bacterial infections usually occur within the next several days to two weeks.​

 

[Marcelo B]

Mmathis, the pond is 36" deep at deepest and 8" at shallowest and it pour concrete in ground.


Thank you very much Usman for your input... how long should I keep the fish that were left in quarantine? and under what conditions do you recommend? water temperature? any medicine? food or not food? with in a large tank or a more confine one?
Now should I do any special treat me to my pond before I put them back? water changes? (remember I have the recirculating well water at all times) add beneficial bacteria? any medicine?

Thank you both!!

 

[Usman]

Mmathis, the pond is 36" deep at deepest and 8" at shallowest and it pour concrete in ground.


Thank you very much Usman for your input... how long should I keep the fish that were left in quarantine? and under what conditions do you recommend? water temperature? any medicine? food or not food? with in a large tank or a more confine one?
Now should I do any special treat me to my pond before I put them back? water changes? (remember I have the recirculating well water at all times) add beneficial bacteria? any medicine?

Thank you both!!

do they show any signs of sickness? i assume they are in quarantine tank atm? if u can give them medicated food thats good or any for immune system , see if they are doing well swimming normally then place one fish in larger pond and so on , keep cycling it . check ur readings . i think fish load is less now it shud b ok .