HELP! pond repaired, fish dying

[Weirdness555]

Hi,

We had a leak in our pond, so we've had pond builders in to repair it and make some changes to the rocks by cementing them in. The fish have been in a small patio pond for about 3 weeks while this has been going on. The pond is now finished, and we're trying to put the fish back in. We had them lined up in buckets, and one of the biggest ones jumped out of the bucket onto the floor, so my mum who was moving them panicked and put all of the biggest fish straight into the pond because she was worried about more jumping out. They then started acting listless so she put them back in the patio pond and they all died. I put this down to nitrate shock from moving into low nitrate water from high, and told them to add a bucket of pond water to the patio pond every hour for the day then move them in the evening. She's done this, then tried to move some of the smaller fish. The first one she put into a bucket of pond water has started swimming upside down and acting listless. She's kept them all in the patio pond and tested the pH, and come up with a pH of 9! Now I'm not sure it was nitrate shock that killed the first ones. I've told them to test all of the parameters and let me know, but does anyone have any ideas?

 

[sissy]

Could be temperature shock also .Plus if the water is city water it needed treated .I put window screening over my tanks and used small hand spring clamps to hold the screening down .Did you have a filter for them when they were out of the pond and airstone in there .

 

[Weirdness555]

The water has been treated with dechlorinator, we moved the filter from the pond to the patio pond with the fish, but a new filter was installed with the repair, so we've moved the filter media across. Now I'm worried about the bacteria dying off because there's no ammonia in the pond, and the filter on the patio pond has no media left, just the sponges. We don't have an air stone but the filter return was causing some aeration and there's been no problem with the fish while they've been in the patio pond. Thanks for replying.

 

[sissy]

Was there a big temperature change between the pond water and where they were stored

 

[Weirdness555]

Well they're both outside, in the air temperature. The patio pond is shallower, so I suppose temperature fluctuates more in there, but they should be the same temperature

 

[Meyer Jordan]

Certainly parameter shock. Need to know the parameters of both the patio pond and the main pond. pH may have played a factor. You are correct, the nitrifying bacteria in your filter slowly die off without an Ammonia source.

 

[Faebinder]

High PH is most likely secondary to ammonia... which means your filter (if any) is not converting enough ammonia to nitrites and so forth. Two things likely happened:

1- The new filter is not cycled so now ammonia is spiking.... (solution: big water changes on the new pond till its cycled).

2- The old filter moved to the patio pond is working but the patio pond is too small and the ammonia is piling faster than the older filter can handle... Ph 9 in the patio pond is a problem waiting to happen even if you feel the fish were fine there (solution: big water change on patio pond if you plan to continue to keep fish in it till you move the fish).

Parameters daily is a must at this point and water changes regularly is a must till the pond stabilizes.. .or you may lose more fish. Pictures of the dead fish may help us identify ammonia burns.

 

[Weirdness555]

There's no fish in the pond so how can there be an ammonia spike? I don't know what the pH is in the patio pond. Is there anything else that could cause a high pH? I've asked my parents to run all tests on both ponds, waiting for that now

 

[Weirdness555]

Results for pond: Ammonia 0-0.25, nitrite 0, pH 9, phosphate 0. No nitrate test in the kit for some reason so I've asked them to look in the loft for my old aquarium kit. Do you know if the chemicals will have degraded or will it still work? Bought it about 2.5 years ago.

 

[Weirdness555]

Results for patio pond: Ammonia 1-2, pH 9, others 0, nitrate unknown. This is since moving the filter media over. I'm really worried about what will happen with ammonia if they stay in the patio pond much longer. Is there anything that could be killing them other than parameter shock? If I can convince my mum they won't all die from some hidden poison she might be able to move them tomorrow morning

 

[Weirdness555]

They are worried about the dust from the cement, the pond was washed out and been filled and emptied 3 times before we started putting fish in, but the water looked milky on the 3rd time still, but it cleared after a day. I know it could possibly push the pH up but could it do anything else? The pH seems the same as the patio pond, our water is very hard. The fish start swimming with their heads pointing downwards.

 

[Faebinder]

It makes sense that it's not ammonia if you havent put any fish in it.

Something has raised that ph really high... if it's not ammonia then it has to be something left over from the construction. I dont know what can be in concrete that is basic but here is an article that shows the rise of ph when adding concrete. So I'm guessing cemeting may have the same material. If calcium hydroxide was involved then i would imagine that would cause the rise of ph.

Do a total water change and see if the ph remains crazy like that. Do it multiple times if you have to till it drops.

 

[Weirdness555]

But the pH in the patio pond is the same so what if that is just the pH of out water? Looking at photos of my aquarium tests the pH out of our tap is 8.2. If there is 0.25 ammonia (It's difficult to tell) where could that be coming from without the fish being in there? If we do a total water change it won't be until tomorrow, it will take a long time to refill so the fish won't be able to be moved until Tuesday or later if it needs doing again. By then all of the filter bacteria will be dead and the fish probably as well from ammonia in the patio pond.

 

[Meyer Jordan]

Parameters in both ponds are nearly identical with the understandable higher Ammonia in the patio pond. Nitrate can also be ruled out. The only other unknown is water temperatures for both ponds. A difference of as little as 5 degrees Fahrenheit can induce stress. Since you have already moved the filtering back to the main pond I would return the fish to this pond ASAP. They may still show signs of stress but should adapt. Just monitor them. If you don't move them the Ammonia build up in the patio pond will certainly kill them.

 

[Weirdness555]

Why can we rule nitrate out? I still think nitrates are the problem, as I've had aquarium fish killed before by nitrate shock when moved into fresh water. The ponds are literally side by side, so I don't think there can be any significant difference in temperature. Should I advise my parents to keep adding pond water to the patio pond all day tomorrow then move the fish? Would that be long enough (2 days) to equilibrate the parameters?