Fish dying from nearby explosion

[mgrasinger]

Hello! Thank you for reading about my unusual problem – I sincerely appreciate any insight.
A house exploded on Saturday about ¼ mile away from my home. Fortunately, there was no apparent damage to my house, but my house shook, and my windows rattled. If you want more information about the explosion, you can google search Plum Borough House Explosion.
I have 2 pond that share the same water – the first pond is 10x6 approximately 18” deep, the second pond is 10x20 and is a zero-entry pond that goes to about 3 ½’ deep. The small pond had about 20 goldfish and the big pond has 3 very large koi and too many goldfish to count. The explosion took place around 10:30am on Saturday. Most of the fish in the large pond stay deep until the sun hits the pond around noon, although there are always a few outliers. The small pond is covered in water lilies to protect from the Blue Herron, so it’s really difficult to see exactly what’s going on in that pond.
On Sunday I noticed 3 dead fish floating in the big pond and 2 in the small pond. I had no sickness or dead fish prior to the explosion. On Monday I had 5 dead fish in the small pond, Tuesday 6 dead in the small pond and Wednesday 4 more dead in the small pond. So here’s my questions:
Is it possible that the house explosion (ground seismic event) could cause my fish to die or should I be looking at a different problem? I had no debris enter my ponds to my knowledge.
If this explosion could cause a fish kill, would it be immediate or could they die over days. As I mentioned, there’s a lot of foliage in my small pond and I can’t get a real good look at what fish are still in there. However, it seems like they are swimming around one day and dead the next.
Would the depth of the fish at the time of the explosion have anything to do with survival rate. Or maybe it could have to do with the volume of water as to how well the shock was absorbed.
Could I expect to have more dead fish – how long would a fish survive this event before dying?
I had 6 neighbors that perished in the explosion and 20 neighbors displaced, this problem seems so meniscal, but I have lost so much control of so many things, I just need to understand why this is happening to my pond fish. Or maybe this problem is coincidental, and I need to be looking at something else. Any thoughtful responses or insight is sincerely appreciated.

[Grumpy]

I have my doubts about the explosion above ground 1/4 mile away effecting your fish.

I would be looking at the water conditions effected by fire suppression chemicals, etc. after the blast.

Have you added any city water to your ponds, perhaps the city bumped up the chlorine in response to possible contamination?

This sounds so bad, so sorry for the loss of so many neighbors...

[two_wheeled]

I think you should start doing water changes immediately. It is very likely that chemicals from the smoke and from putting out the fire have contaminated your pond water.
Also, keep good records in case the insurance company needs to cover your losses.

[coolwon]

If your house shook,and the windows rattled in a house close to an explosion that killed
six people and displaced 20 people, it must have been a big explosion.
I think the percussion wave from the explosion through the ground killed the fish.
You just have to look at the aerial views of what was once peoples homes.
The percussion wave must have stressed out tiny little unsuspecting fish, swimming in the
ponds

[mgrasinger]

Thank you for your thoughts! I truly appreciate it. My local pond store is also perplexed on what could be causing the issue. I had 6 more dead fish this morning and 3 of them were in my big pond. So, I took a water sample to the pond store, and he suggested a 50% water change, salt, and baking soda. So that's what we did. Hopefully that resolves the issue!

[coolwon]

Has your fishes swim pattern changed,since the explosion in either pond?

Do you think the water condition has taken on a new look in any way?

Clarity,smell,floating particles on the surface?

[RichToyBox]

Because water quality is the most important thing when it comes to fish health and recovery, I suggest you invest in a good test kit, like API FRESHWATER MASTER TEST KIT with the addition of an API KH test kit. I trust myself to run the test frequently, and know how things are changing, over any pet store. Unless there was nitrite present, salt is of little use, but it does protect fish from nitrite poisoning with the addition of about 1 pound per hundred gallons. It does not have to be aquarium or pond salt, just any good salt with water softener salt from the hardware stores being the cheapest. The kH is the most important test in my opinion, as a good KH of over 100 ppm will keep the pH rock solid, probably around 8.3, and if it is rock solid, then the fish are happy, the bio bacteria are happy, and the water numbers are good and fish healthy. Ammonia is the most toxic and can be treated with one of the dechlor products that bind ammonia.

[mgrasinger]

I just wanted to thank everyone for your input and post a quick update on my pond. First, I left out a very important detail on my first post that I wanted to add. It rained cats and dogs the night of the explosion. Honestly, I was in such a state of shock I had completely forgotten that it rained that night until a few days ago. All told, I lost about 40 fish, mainly babies to 2 years old, although I did notice some babies today that survived (so far) and the carnage has seemed to subside. I had my water tested and it was very acidic, so we did a 50% water change, added baking soda to balance the PH and added some additional salt.
My uneducated conclusion is twofold. I can definitely see how the small pond would have experienced a more intense seismic event than the larger pond. I think the larger mass of water in the big pond would have absorbed more shock than the smaller pond. Thus, the fish in the smaller pond were likely more stressed than in the larger pond. The toxins in the air were brought straight down into the ponds the night of the explosion by the rainstorm. The toxins coupled with the stress caused the fish kill. We ended up losing all the fish in the small pond and only about 10 in the larger pond.
Conclusion to anyone that experiences a simple house fire or wildfire nearby and a subsequent rainstorm – don’t wait on that water change. I wish I had realized that sooner!

[cindy]

Sounds like a ph crash. Sorry about your neighbors. Saw it on the news.

[KingstonKoi]

I keep thinking about your unusual situation. It sounds like you had the perfect storm of three incidents, any of which might have killed or stressed your koi. We are always warned not to break ice when a pond is iced over, as the impact of pounding on it can stress the fish to the point of killing them. So it’s not hard to imagine the ground shock from an explosion could do the same. Then you have toxins falling in the water which could kill the fish. And finally heavy rain which causes a pH crash, another killer of koi. In hindsight it’s a wonder that any of the fish would survive. Very unusual situation.

[fly4koi]

The bad Canada wildfire smoke finally made it to my area about a month ago, then after a few days it rained, which cleaned the air but I'd imagine the rain water being very dirty.
Coincidentally my shiro utsuri developed an injury near its tail, so I'm not sure if that's related, I mentioned in the other thread that BSDT shouldn't have helped but it seems that it did (2 times), so I don't know.
The water quality tested ok after the rain, though my kit doesn't test anything other than the typical ones.

[gmessler]

What is the bottom of your pond like? Do you have rocks? Is there a lot of organic debris in the bottom?
I kind of wonder if the shock released a bunch of hydrogen sulfide into the water.