All my fish are dying...

[DerSchoeneBahnhof]

Ugh, since couple of weeks, every day I catch a few dead fish at the surface. No expensive fancy koi thankfully, but the pond was bristling with life before that, including lots of newborn.

Should I test the water? Since the rains have stopped here I have started again topping off the pond with a hose, same as every year and wasn't a problem before.

One change I noticed is the water became suddenly completely clear, I can see all the way through the bottom (2 feet deep). Maybe the algae are dying and the fish have nothing to eat? The remaining fish appear lethargic and spend hours being stationary.

Any ideas?

 

[JRS]

Sorry to hear about your problems. Some more info would help, as well as any testing info, clear water is not always healthy. Ammonia nitrite, pH and KH would be good, or whatever you have on hand. Die offs could be environment-contaminated chemical run off, pH shock, poor water conditions.
Algae die off could affect oxygen levels, usually bigger fish go first though. Healthy fish do not starve all of a sudden so I doubt food is your issue. Any new livestock introductions, possibly bringing in a disease organism? Do you dechlorinate your top off water? I have heard stories of some water utilities changing from chlorine to chloramine, more toxic and persistent, that have caused problems.

 

[GBBUDD]

Ugh, since couple of weeks, every day I catch a few dead fish at the surface. No expensive fancy koi thankfully, but the pond was bristling with life before that, including lots of newborn.

Should I test the water? Since the rains have stopped here I have started again topping off the pond with a hose, same as every year and wasn't a problem before.

One change I noticed is the water became suddenly completely clear, I can see all the way through the bottom (2 feet deep). Maybe the algae are dying and the fish have nothing to eat? The remaining fish appear lethargic and spend hours being stationary.

Any ideas?

pictures of the pond and filter

 

[DerSchoeneBahnhof]

I'll follow up with pics tomorrow...

Ok, so I made one mistake, while working on my bog fountain sitting right next to the pond, I applied some Preserva Wood on some unprotected plywood edges (the rest was covered with a tarp because rain and not yet painted). The brush sent tiny droplets into the pond, I could see a thin oil layer on top which quickly dissipated (pond is about 900 gallons). If that is enough to cause a massive fish die off then it's my responsibility.

However, some fish have started dying before that so I dunno.

 

[Laaf]

I applied sealant to a bridge over a 600 gallon pond with goldfish. In spite of my caution, some drops fell in and spread a petroleum looking irridescent area on the water. No fish died. I do not think the small amount of sealant is your problem! I have seen goldfish living in a parking lot overflow drainage areas that drained all the oils and junk from the parking lot. It was near a Petsmart and I wondered if the fish were released from the store.

With recent rains, either a change in PH or run off of fertilizer or chemicals from surrounding areas would be on my list of possibilities.

Did you do any kind of algae chemical treatment?

I am sorry for the losses. It is always disturbing to lose any.

Yes test your water, it may be informative.

Do you have aeration?

 

[jgrandmont]

If I had to guess without knowing any other details, I'd say that it was the wood preservative. Fish are highly sensitive to chemicals.

 

[sissy]

get some quilt batting when yu do that to catch anything . Put a pump with a hose going into a extra tank and then all the water should be allowed to go back into the pond filtered . I keep a tank handy with a tank adapter in it to dore that when i clean and net the bottom of the pond after winter or after a windy storm . You never know what can blow into a pond .

 

[DerSchoeneBahnhof]

Here is pic. The bog fountain is still covered with tarp until I paint it (this time will have to be careful).

Mechanical filter on the left uses polyfil and sponges. No aerator. I need to do some homework on how to test the water.

 

[Laaf]

I would get the bog up and running asap. It will greatly increase your filtration and aeration. Sure paint or seal it first if you have time. But even untreated wood will last for years and years. Whatever is causing fish to die, increasing filtration and a bog will improve your water quality and decrease the chance of more fish dying.

 

[sissy]

you can get test kits for pond water online . You just tae a sample of you water and drop the amount of drops in each vial and wait for the color to change API TEST KITS ARE EASY

 

[DerSchoeneBahnhof]

I would get the bog up and running asap. It will greatly increase your filtration and aeration. Sure paint or seal it first if you have time. But even untreated wood will last for years and years. Whatever is causing fish to die, increasing filtration and a bog will improve your water quality and decrease the chance of more fish dying.

Like Leonardo would say, I concur. I need at least to paint the exterior sides which are plywood (not structural here, but still), and plywood doesn't like moisture untreated.

Then I will test water and add more fish after that.

Just too many garden projects (I just finished a chicken coop, and these stinky girls really had to move outside).

 

[mrsclem]

Your pond is 900 gallons? How many koi and how many goldfish? Its possible that your fish load has exceded your filtration. Get the test kit and post the results.

 

[DerSchoeneBahnhof]

No koi. About 30'ish goldfish at most, small ones. Will get test kit.

 

[DerSchoeneBahnhof]

Well, I have got a bigger problem. I think my pond (concrete, in ground) is leaking. I topped off on Tuesday, today 2 days later it already lost 2 inches. No way this can be through regular evaporation, not a lot of wind and temperatures are still a max of 68 F. Oh boy...

 

[j.w]

Well, I have got a bigger problem. I think my pond (concrete, in ground) is leaking. I topped off on Tuesday, today 2 days later it already lost 2 inches. No way this can be through regular evaporation, not a lot of wind and temperatures are still a max of 68 F. Oh boy...

No waterfall turned on right? Leave it off and let the water in the pond go down as far as it will unless of course it looks like it is going to empty the pond. When it goes down till it stops then check all around the line where it stops to see if any bad spots. Then you will have to somehow patch that area. I don't know about how to go about that tho so hope someone else can help after you find the spot where it is leaking. If it ends up being on the bottom, oh boy! You will have to remove the fish and put in a big kiddy pool or ? while you try to fix it. Save most of your pond water in non toxic barrels or tubs so as not to shock the fish when putting them back into the pond.