HELP: anything I can do to save fish?

[Brock99]

I cleaned my pond yesterday and now realize I changed out way too much water and removed way too much algae and good bacteria. Lesson learned the hard way as I lost 1 fish already (about 36 hours/1.5 days after water change). My last 3 guys are clearly stressed and swimming around weakly almost already floating at top. I don’t believe it’s an oxygen issue as I’ve had fountains going religiously since the clean and have gotten all levels back to normal according to test strip and added beneficial bacteria. MY QUESTION: anything I can do to urgently save my last 3 guys, or do I just have to wait it out for them to die at this point? thanks!

 

[Mmathis]

Hello and welcome! Unfortunately, we all make mistakes, but FORTUNATELY, we do learn from them.

Can you give us a little more information about your pond: size, type of filtration, etc? How long has this pond been up and running? Goldfish, koi? Did you dechlorinate the water?

If you don’t already have a source of aeration (IOW, surface water movement), you might add some extra air via an air stone or letting an extra pump squirt water to the surface. Maybe don’t feed for a while.

 

[Brock99]

Pond size is just shy of 1000 gallons it’s 2 ponds that has a filtered box with pump that goes from bottom pond to waterfall box to spill over into the top pond then back to bottom. I have a fountain with uv and filters in top and bottom pond as well as a spitter in top pond. I had 9 koi originally and lost 5 to a couole dying during transfer and a couple jumping out until I figured out I needed a stone wall around the pond. I lost one that was never found guessing it was eaten by another koi being a runt. Pond has been up for 3 years or so but finally got koi 3 months ago. The remaining 4 were going strong until I did this unfortunately. My test strips say it’s perfect I don’t need to dechlorinate since I’m on well water. I will stop feeding and I’m picking up a buffer today to try and help. The water is starting to get back to normal temp since it’s been hot yesterday and will be today and it’s in direct sun.

 

[Brock99]

@water this was when I first got it all put together and was in the process of getting water right which it was shortly after I had build up on top pond from no fish in top pond which is why I did a water change up their which caused all of this and I forgot to mention I have lilys in bottom and cat tails on top pond

 

[Brock99]

@water this was when I first got it all put together and was in the process of getting water right which it was shortly after I had build up on top pond from no fish in top pond which is why I did a water change up their which caused all of this and I forgot to mention I have lilys in bottom and cat tails on top pond

And I have bacteria balls in all 3 filter boxes

 

[Brock99]

@Mmathis forgot to tag you in my responses, sorry. Thanks for your reply.

 

[Mmathis]

This won’t solve your current problem, but it might head off future problems. Please don’t take this wrong, but your ponds are too small for koi. Koi need a lot of room, and they produce a lot of waste. They need a lot of filtration. A pond’s biofilter will quickly become overwhelmed which is not healthy for the fish. A few suggestions:

1. Consider smaller fish like goldfish (or a larger pond)
2. add shade — sunlight REALLY causes the algae to happen
3. add plants! Lots of plants!
4. add water movement such as a waterfall, air stones, or even a fountain pump to move the water around and help aerate it.

Where do you live?

 

[WaterGardener]

I think there must be something else going on here. I don't think it's possible to change out too much water. I've had to do nearly 100% water changes in the past with no I'll effects for the fish.

There is very little beneficial bacteria in the water. It grows on hard surfaces like filter material. Changing the water won't compromise the bacteria.

Also, the bacteria you buy in a bottle is not the same as the bacteria needed for the nitrogen cycle. That bacteria won't survive sitting on a shelf and sealed up with no oxygen.

Was there a major difference in the water parameters for the pond and the well water you added? Was there a difference in pH or KH?

I also doubt you removed too much algae. Many koi ponds are kept as pristine as possible with no algae, or as close to that as possible.

Someone here just did a complete clean out of their pond and had no problems whatsoever. @Lisak maybe? Sorry, don't remember off the top of my head.

What buffer are you referring to and what do you expect it to do?

 

[Brock99]

This won’t solve your current problem, but it might head off future problems. Please don’t take this wrong, but your ponds are too small for koi. Koi need a lot of room, and they produce a lot of waste. They need a lot of filtration. A pond’s biofilter will quickly become overwhelmed which is not healthy for the fish. A few suggestions:

1. Consider smaller fish like goldfish (or a larger pond)
2. add shade — sunlight REALLY causes the algae to happen
3. add plants! Lots of plants!
4. add water movement such as a waterfall, air stones, or even a fountain pump to move the water around and help aerate it.

Where do you live?

I think the picture is throwing you off it has lots of filtration now and plants and I can provide a new one when I get home. I have plants I planted around it for shade in the future. I live in northern virginia.

 

[Brock99]

I think there must be something else going on here. I don't think it's possible to change out too much water. I've had to do nearly 100% water changes in the past with no I'll effects for the fish.

There is very little beneficial bacteria in the water. It grows on hard surfaces like filter material. Changing the water won't compromise the bacteria.

Also, the bacteria you buy in a bottle is not the same as the bacteria needed for the nitrogen cycle. That bacteria won't survive sitting on a shelf and sealed up with no oxygen.

Was there a major difference in the water parameters for the pond and the well water you added? Was there a difference in pH or KH?

I also doubt you removed too much algae. Many koi ponds are kept as pristine as possible with no algae, or as close to that as possible.

Someone here just did a complete clean out of their pond and had no problems whatsoever. @Lisak maybe? Sorry, don't remember off the top of my head.

What buffer are you referring to and what do you expect it to do?

PH alkalinity and carbonate were low and I did the baking soda method and got the test strips back to normal within a few hours. I think the main issue was how cold the water that was put into the pond compared to what was taken out. API pond stress coat pond water conditioner (buffer) is what I purchased as a last resort to save the remaining fish.

 

[j.w]

@Brock99

 

[Brock99]

@Mmathis @WaterGardener @j.w @Lisak1


I wish I could attach a video but can’t figure that out - this was my last little guy today (3 days after cleaning). He was swimming on his side in circles and upside down in this photo - like he had no control over his body/movement. He was still alive in this photo, swimming around in circles and getting stuck everywhere, even upside down (again still alive). Any idea on what I did that caused this? I’ve seen swim bladder with similar symptoms but I was under the impression that’s a disease that happens over time. All the fish did this before they died and they were all perfectly fine before I did the water change and pond clean out.

I just want to avoid this in the future and know what caused it. Thanks again!

Edited to add: I added about 9-12 goldfish yesterday and they are all in perfect shape so far. Haven’t lost a single one.

 

[Mmathis]

Just MHO, but the last thing you needed to do was add more fish! You need to get your current situation under control first. Then when you get that sorted out, add new fish, but quarantine them first. New fish might ”look in perfect shape,” but they will be stressed by the move and this will make them more susceptible to illness…..and it stresses your current fish, as well.

 

[Brock99]

Just MHO, but the last thing you needed to do was add more fish! You need to get your current situation under control first. Then when you get that sorted out, add new fish, but quarantine them first. New fish might ”look in perfect shape,” but they will be stressed by the move and this will make them more susceptible to illness…..and it stresses your current fish, as well.

@Mmathis My test strips are showing perfect results, my water is completely normal now. I added the goldfish on top pond that was vacant, not the bottom where the last koi was anyway, who has already died.

Goldfish or not, that really doesn’t help me with my initial question - which is what happened to my koi fish and caused them to die after my water change. That’s what I’m really trying to figure out and ask advice about.

 

[WaterGardener]

If you raised the pH and alkalinity too quickly, it might have been the cause. Those should be raised gradually and not all at once. It stresses the fish too much to have big fluctuations in pH. I don't know how low it was or how much it was raised, but large changes should be made over days not minutes.

No one can say exactly why it happened, but I think that could be a possibility.