Val and I are in total shock.

[MitchM]

The largest temperature swing I see for your area during that weekend was from +9C/48F down to -2C/28F over an 18 hour period. Humidity was 70 - 90% and winds were about 20km/h or 13 mph.
Those are air temperatures of course.
Wind chill would have been a brief -4C/25F at it's worst.
Your ponds are about 2000 gallons each?
It would be helpful to know what water temperature readings you had before, during and after the storm.
Healthy fish can withstand an instant drop of 3C/5F, so your pond over 18 hours would have to had a heck of a change in temperature in order to kill.

I'm just not seeing a situation that could cause rapid cooling of the water, enough to kill fish.

.

 

[callingcolleen1]

Dave I never mocked you and I totally understand this was a very rare storm for all of the UK as I have seen many pictures. I do understand that you guys are not used to dealing with a rare winter storm event of historic proportions. Many in the UK were shocked by "The Beast from the East" storm as was lots of people around the world.

Last night was down to below minus 13 Celsius and I never bothered to plug in my hratet now for many days as daytime temps are nicer. Fish were all fine. @CE she runs just pump with lots of thrashing water action to keep her pond open and they do well too.

Its ok Dave, we are all still shocked as well that so many of your fish passed.

Wishing you and Val all the best as you recover from this tragic event and their are other fish out there to light back up your life and your pond.

 

[Lisak1]

I'm just not seeing a situation that could cause rapid cooling of the water, enough to kill fish

What you're saying makes sense to me Mitch. I also think there's confusion in the terms "supercool" and "super chill". Supercooling - as has been stated many times - can't happen to pond water. You can only supercool - or take water below the freezing point without it actually forming ice - water that's free of minerals. That's not pond water. "Super chilled" isn't a thing that has any real definition, unless it's "my pond got really cold really fast". I don't know that it matters to fish how fast the pond cools off. But in any case, water is not like air - you can have tremendous drops in air temperature in a short period of time. Water is going to cool at a much more slow and steady pace. Air temperatures aren't really pertinent to the discussion anyway, except as they affect the pond temp. Your fish could care less how cold it is in the air since they are able to stay at the bottom where the water is the warmest and temperature stays the most stable.

 

[callingcolleen1]

Yes its true, water could not have been too cold for koi as my koi sit in water of barely 1 degree celsius right now as they always do. That one heater I have heats 4 big ponds and it really should only heat one pond but my flowing water cuts the ice down in upper ponds and I never worry that water is too cold even at minus 45 Celsius. I only worry that they get lots of oxygen as that is what kills them, not the ice cold water or mine would have been dead long ago.
I remember well Your friend from BC Canada and she only had heater I believe. Bubbiers freeze off after -20 Celsius and without moving water the heater can ice over with snow and ice, and water may be warm under the ice, but without moving water they quickly run out of oxygen.

 

[BarbO]

Dave, how did other ponds in your area do during the winter storms? Did others lose fish too? Once again, I am so sorry about your fish loss.

 

[callingcolleen1]

here are some ponds from the UK that went through same storm as you @dave54
its a good video and shows you they ran their pond all through the storm and it got lots of ice and snow. Koi fish were all fine. Same storm ...

All the people I know that lost koi during winter all had the same thing in common... the water was not circulating. Some people just used a heater and a bubblier {same as aerator } which froze off during extreme cold. I noticed my aerator quit working around -30 Celsius {about -22 Fahrenheit} or so... I still had my pumps circulating the four connecting ponds but was experimenting with the aerator.

I found a koi pond in same area as Dave @BarbO
Same storm that hit @Dave 54

NOTE air pump - Canadian term
bubblier - UK term ? (Dave)
aerator - American term but now in use in Canada, but we here mostly still call it an "air pump"

 

[Lisak1]

I don’t know that I would call that “lots of ice”. Was that the extent of it?

 

[Mucky_Waters]

Even though Colleen may not fully understand the brewing process of beer I believe her logic is sound regarding how unlikely it is that the passing of Dave's koi can be attributed to rapid cooling alone.

I have a question that is slightly off topic but relevant to this thread, can we expect to see any more posts in this forum from @brokensword ?

 

[callingcolleen1]

Even though Colleen may not fully understand the brewing process of beer I believe her logic is sound regarding how unlikely it is that the passing of Dave's koi can be attributed to rapid cooling alone.

I have a question that is slightly off topic but relevant to this thread, can we expect to see any more posts in this forum from @brokensword ?

Thats cause I drink wine ha ha ha! Going to have one cause reading about the fish that died stresses me out so it's "stickly medicinal" and my day off too. And did I ever work hard running at work to fill the selves

 

[callingcolleen1]

I don’t know that I would call that “lots of ice”. Was that the extent of it?

Their were other videos from UK and some ponds really froze pretty hard. I will look for that one too and post later cause I am running off to see my mom right now.

 

[callingcolleen1]

Dave and I are old school and back a long time ago everybody shut their ponds down and back then when I first started with a pond, everybody though the koi would freeze and the water would get "super chilled" if they left the pond run. I got so much grief and ridicule just trying to tell people long time ago to leave the pond pumps run and many people still believe that Koi cannot winter in ice cold running water. Lots of people in the UK run a heater on a "cool summer night" when flowers are still blooming to this day! I will have to find that video too.
But this video is from the UK as well and most are now running their ponds all winter. This guy is very good.

 

[callingcolleen1]

I found that other video of a bigger larger pond completely frozen expect the waterfall is still running. The guy does not appear worried as he has done this before and I think his fish will be fine as his water is still running.

Frozen pond after the "Beast from the East" Storm in the UK

 

[DrCase]

Sorry to read this about your koi Dave.
Have you tested the water coming out of your De chlorination filter ?

 

[Mucky_Waters]

I have a question that is slightly off topic but relevant to this thread, can we expect to see any more posts in this forum from @brokensword ?

Anyone ... ???

 

[adavisus]

A thermometer on a rock and a length of string might be useful, to see if bubblers are causing deep water to chill.

If there is a high salt content, ice crystals may be choking gills if well below freezing air temps are stirring up the deep water