Fish Died

[clark kent]

I've had the thousand gallon pond for about six months now (existing pond with the house I bought.) There were initially eight goldfish in the pond, now the number is up to about seventeen. They all seem to be doing well. The water is well filtered and aerated, and the chemistry is excellent.

So yesterday morning I noticed one of the smaller fish not swimming upright in the water and appearing to be gasping for air. By the afternoon, it was on its side, dead. No signs of anything that would cause this. The rest of the fish are doing fine. I rechecked the water chemistry and it is fine. Nothing else out of the ordinary.

I'm a bit new to this, and I just wondered what happened. Does this just happen occasionally? Any ideas?

 

[poconojoe]

Sorry to hear about your fish.

There are many reasons this can happen. You need to give more information for anyone to begin to diagnose what might have happened. Even then we may never know.

What did the dead fish look like? Any scars, abrasions? Did it's scales look normal or were they pineconing? Was the fish bloated? How big was this fish? How long have you had this fish? Do you know it's age? Do the rest of the fish seem to be unaffected? Could a predator have visited the pond and injured the fish?

How are you checking the water chemistry, what tests are you performing and what are the exact figures? The liquid tests kits are far superior to the ones that use test strips.

Describe your filtration and aeration. Are they running 24/7?

Do you have any plants in your pond? Plants are an important part of the ecosystem.

So, as you can see, we may never know what happened to the poor guy (or gal). Too many variables. I'd say as long as it's not some kind of big outbreak and your other fish are fine, just chalk it up as something that just happens in nature. Just make sure your water parameters are within acceptable range. Post up your test figures and hopefully the chemists here can give advice on that.

If you can post some pictures of your pond, that would be good too. Plus, we like seeing other people's ponds!

Good luck and I hope the rest of your fish are OK.

 

[Mmathis]

What @poconojoe said. Also, so sorry for your loss!

One thing to always keep in mind — sometimes, no matter how careful you are — fish just die.

 

[clark kent]

Climate zone 7a.
1000 gallon pond.
4000 gallon per hour pump.
Pondmaster Proline 4000 pressure filter.
45 watt inline UV filter.
3 foot high waterfall.
There are a few water irises and some green algae in small patches.

The water is clear. I am using API liquid test kits with no out-of-date chemicals. The water chemistry is consistently as follows:
Chlorine/Chloramines 0.
pH 8.5
kH ~100 ppm.
Ammonia <.25 ppm.
Nitrites <.25 ppm.
Nitrates ~ 5 ppm.
Phosphates <.25 ppm.

When I took possession of the house about six months ago, there were eight fish in the pond, ranging in length from about two inches to six inches. I have not been feeding them, and they have survived well on insects and algae. There are now approximately seventeen or eighteen fish from two or three separate batches of eggs, many of which have not yet changed color. They all appear entirely normal and healthy.

The one that died was one of the original small ones, about two inches long, age unknown, I'm guessing a year or two. It looked entirely normal, no scars, no abrasions, no protracted scales, no bloating, no trauma of any kind apparent.

All the other fish are still doing just fine.

I do not think that there is anything out of the ordinary in these details that could explain what happened. I'm not necessarily looking for an explanation. I just wondered if this sort of thing just happens occasionally.

 

[CometKeith]

Hi Clark. I’m sorry about your little fish. So when I see a fish gasping for air my first thought it’s not getting enough dissolved O2 in the water. This can be from damaged gills from untreated chlorinated water or insufficient oxygen in your water. Disease can cause this too. Even though you have a waterfall you have nothing to lose by adding another water pump to splash water or an air pump. I have found there is never enough water movement in any pond. My pond is a little larger than yours but I have an air pump, a bog pump, two water pumps splashing water, and a bead filter and pump that splashes water too. My pumps are turning over almost 4 times the amount of water in my pond per hour. I have never had a fish complain!

 

[AlyssaFish]

In most cases, it's not normal for a single-tailed goldfish like a common or comet to drop dead for no apparent reason. This is less true for very young fish, fish that were obtained from a disreputable source (like a feeder tank), or a weaker fish who has gone through several severe periods of illness in the past and are simply less hardy than others because of it.

In a thousand gallon pond that has been operating for 6 months with the parameters that you described and none of the other fish showing signs of illness, it seems unlikely that this is a sign there's something that's wrong with your pond.

The one thing that is a little off about the pond is how it has so few fish in it, despite being (from the sound of it) such a suitable environment. There could be several explanations for that. The ideal thing to do would be to contact the owner and ask where the fish came from, when they were purchased, that sort of thing.

It's possible that they had other fish in the pond and removed the ones that they liked when they left. Or that they built this pond this year and bought the fish of multiple sizes to populate it. Or perhaps there IS something wrong with the pond and it has been preventing the population from blooming... or maybe a predator took other pond fish before you bought the house. Maybe the incident was so tragic it's why the owner decided to rehome themselves--they couldn't bare to be reminded of the tragic incident every day they walked into their garden!

Smaller fish can also have a problem with flukes. They can be fatal. If it's immune system was weakened for some reason (maybe it got rejected during breeding season and felt sad), it could have succumbed to gill flukes. That could explain the difficulty breathing.

 

[clark kent]

Thank you for that information. When I bought the house in early spring, it had sat unoccupied for over a year. The filter/waterfall pump had failed, and it appeared that the pond had been without filtration or aeration for some time. I suspect that those eight goldfish were the last survivors of a much larger population that was once there.