Temperature difference when moving fish

[SimonW]

Hello friends:

I have learned that a temperature difference of more than 3 centigrade is dangerous when moving fish from one water to another.

What I am wondering is: Is it equally dangerous to move fish from colder to warmer water as to move them from warmer water to colder water?

Today I added tap water of 19 centigrade into the outdoor pond with water of 5 centigrade, and I found that all the koi in the pond congregated around the inlet. They must be enjoying the warmer water there which can be more than 3 centigrade warmer than the rest of the pond water!

May I guess that it is more tolerant when moving fish from colder water to warmer water? I wonder if you can tell me your record of temperature difference when moving fish. Particularly from colder to warmer water. It is very interesting for me because soon I will need to move my koi indoors, and that is to move them from colder water to warmer water.

Thanks!

[fly4koi]

I believe going from warm to cold is more critical, always acclimate your fish.

[coolwon]

Hi Simon, your fish would be benefiting from the slow warmer water entering the colder water housing the fish which would be slowly equalizing

the two temperatures gently.

It would not be a drop into shock change in the temperatures.

Humans feel the cold sudden difference with a gasp,fish have to accept it until their bodies acclimatize to the difference.

Which is a shock and very stressful.

I acclimatize new fish, by lowering their plastic carrier bag into the new home water and swapping cupfuls of the two water for the pH and the

temperature difference until equal.

It is customary to arrive at a Koi show, with your fish in a long plastic bag that suits the length of the fish and an amount of water to just cover

the dorsal fin.The fish is then lowered into the vat water and allowed to float and acclimatize for an hour or so to equalize the two temperature.

The benching team arrive and place the fish into a floating measuring container to go over it for any abnormalities, why it should not be entered

into the show.

It is measured, the length and its classification confirmed. All good to go.

Good luck.

[kdh]

You can move fish from cold to warm without much of a problem. I have done 10 degrees with no problems. And others have done more. As there metabolism is able to ramp up quickly. If I remember correctly just in 4 hours, However warm to cold is much harder for there metabolism to adjust to. I have done around 10 drop and they went to the bottom. They didnt like that. Again if I remember correctly it takes them about 20 hours to adjust from warm to cold. I had no problem with a drop of 5 degrees however.

Just guessing but it might depend on what temperature a large drop or rise is occurring.

[SimonW]

You can move fish from cold to warm without much of a problem. I have done 10 degrees with no problems. And others have done more. As there metabolism is able to ramp up quickly. If I remember correctly just in 4 hours, However warm to cold is much harder for there metabolism to adjust to. I have done around 10 drop and they went to the bottom. They didnt like that. Again if I remember correctly it takes them about 20 hours to adjust from warm to cold. I had no problem with a drop of 5 degrees however.

Just guessing but it might depend on what temperature the drop or rise is occurring.

Actually I have done >15 degrees in difference from cold to warmth. I simply took the cold water with fish indoors into a tub and blew air into it until the temperature difference was less than 3 degrees.

I have also done the opposite, from warmth to cold, about 10 degrees' difference, but it was a total failure. I did it in the same way: I put the warmer water with fish into a tub outside, and next morning I found 9/10 of them dead.

But my real question here is different: The maximal temperature difference koi can take directly from colder water to warmer water, without equilibration. My guess is more than 3 degrees.

[coolwon]

I value my fish.

I take great care of my livestock.

[kdh]

Actually I have done >15 degrees in difference from cold to warmth. I simply took the cold water with fish indoors into a tub and blew air into it until the temperature difference was less than 3 degrees.

I have also done the opposite, from warmth to cold, about 10 degrees' difference, but it was a total failure. I did it in the same way: I put the warmer water with fish into a tub outside, and next morning I found 9/10 of them dead.

But my real question here is different: The maximal temperature difference koi can take directly from colder water to warmer water, without equilibration. My guess is more than 3 degrees.

You well have to try and find a research paper for information if there even is one . Good luck with that.

[SimonW]

I value my fish.

I take great care of my livestock.

Right, if your fish are valuable or you really love them. Otherwise, please follow the law of the nature: 99 999 of every 100 000 hatched koi fish are supposed to die, lest you will be ruined by all your swimming pigs.

[coolwon]

You have kept fish since 2018!

You have 1,212 posts.

The majority are probably,looking for help to doctor your sick fish.

Read all the guide lines,the do's and don't on how to keep your fish healthy and happy, and watch them growing in leaps and bounds for the next

Koi show.

You add 10 fish from warm comfortably surroundings, to cold water and 9 out 10 fish die.

You experimenting with fish like the chimps and rabbits held in captivity to decide if the shampoo is safe for human use.Will it burn their eyes.

No fish keeper hobbyist is interested in the temperature difference parameters of will they live or die.

These are ornamental fish,they are not in captivity by choice.

You are just plain cruel.

Rule number one, acclimatize and quarantine any new fish in a quarantine tank with filtration etc,to keep them healthy and happy while in

quarantine.

They must be valuable or you would not be throwing your money away on the cost of the electricity, water, food and the set up you keep your

fish in

The law of nature is in the wild, regarding the numbers that make it to adult hood to carry on with the species.

[SimonW]

You have kept fish since 2018!

You have 1,212 posts.

The majority are probably,looking for help to doctor your sick fish.

Read all the guide lines,the do's and don't on how to keep your fish healthy and happy, and watch them growing in leaps and bounds for the next

Koi show.

You add 10 fish from warm comfortably surroundings, to cold water and 9 out 10 fish die.

You experimenting with fish like the chimps and rabbits held in captivity to decide if the shampoo is safe for human use.Will it burn their eyes.

No fish keeper hobbyist is interested in the temperature difference parameters of will they live or die.

These are ornamental fish,they are not in captivity by choice.

You are just plain cruel.

Rule number one, acclimatize and quarantine any new fish in a quarantine tank with filtration etc,to keep them healthy and happy while in

quarantine.

They must be valuable or you would not be throwing your money away on the cost of the electricity, water, food and the set up you keep your

fish in

The law of nature is in the wild, regarding the numbers that make it to adult hood to carry on with the species.

Thank you for your honest opinion. But I wish that we could let our brain instead of our feelings direct our actions.

It is silly that I have to explain that I didn't kill them intentionally. Instead they were culled fry that I could not kill due to my compassion. I had tried to give them away but could not find anyone to take them. Therefore I intended to move them out again into the pond for over-wintering there. I had indeed moved them indoors, only to realize that I did not have enough space for them, lest I will jeopardize the koi I want to keep.

You may have noticed that I do home-breeding and every year I get hundreds of koi that I cannot keep. If you were my neighbor I would let you take care of them because you are so kind

Anyway, some science about fish: Fish don´t have, or have very little sensory bodies for pain, so if other people can do experiment with rats and mice, why we cannot do with fish which cannot feel pain or far less pain? Fish also lack cerebrum therefore cannot feel death anxiety. Therefore there is no inhumane way to kill a fish.

By the way, on YouTube you can see that the Japanese breeders just throw the culled koi into a bucket with very little water. I am not sure it is a better way for fish to die, by suffocation instead of cold.

[Matt24]

I don't know how big of a temperature swing is too big. But consider if it would be helpful to pump water through a hose from your outdoor pond into your indoor tank just before you move the fish indoors. Then they could warm up with the water, a little more gradually.

[coolwon]

Winter basement pond heater.

I would consider the smallest swimming pool heater for my winter indoor pond warming requirements.

The electricity power consumption would be the equivalent of a small room air conditioning unit.

Place the pond on polystyrene or urethane insulation to reduce the loss of heat into the cold concrete floor.

Wrap a layer of fiber glass wool around the perimeter of the pond wall if it is round,Polystyrene if it is straight edged,to stop the infiltration of the

cold conditions in the room.

A bubble wrap blanket just laid on top of the mesh, which should be stretched over the pond to stop the jumpers.

You don't have to make the water temperature,sauna warm conditions.

Adjust the thermostat temperature to cycle the unit off at the temperature, that the fish are not huddled and motionless on the bottom.

Give them some life.

You want to keep Koi?

A never ending life of pay,pay,pay.

[KingstonKoi]

I really miss Steve Hodgin, who would have stepped in with the correct answer fairly quickly. Rather than letting this run off the rails. The answer is 3°C or 5°F when going to a lower water temperature. Generally, when receiving new Koi and moving them between waters, you float them in the bag to let them acclimate to the new lower or higher temperature for 20 to 30 minutes. Koi are or pikothermic, which means their body temperature follows the water temperature. More than 5°F is stressful for them to adapt to. In fact, there is one reputable West Coast online dealer who will not release their fish until April, and only after you state your water temperature is within 5° of their pond temperature. And it is true that fish can adapt to a higher temperature much more quickly than a lower temperature. For those who want to know more and are not sure of the answer to questions like this, highly recommend the various courses available from K.O.I. online.

[coolwon]

I really miss Steve Hodgin, who would have stepped in with the correct answer fairly quickly. Rather than letting this run off the rails. The answer is 3°C or 5°F when going to a lower water temperature. Generally, when receiving new Koi and moving them between waters, you float them in the bag to let them acclimate to the new lower or higher temperature for 20 to 30 minutes. Koi are or pikothermic, which means their body temperature follows the water temperature. More than 5°F is stressful for them to adapt to. In fact, there is one reputable West Coast online dealer who will not release their fish until April, and only after you state your water temperature is within 5° of their pond temperature. And it is true that fish can adapt to a higher temperature much more quickly than a lower temperature. For those who want to know more and are not sure of the answer to questions like this, highly recommend the various courses available from K.O.I. online.

Running off the rails is every bodies view.

Makes it more interesting.

The recognized way to acclimatize fish to the water they are about to be introduced to, is to be patient,lower their bag into their new water

home.

Allow the bag to float,long enough for temperatures to equalize. The length of time would be the temperature difference between the two waters.

Lift each fish out of the bag and transfer by hand into the new pond water.

After lifting all the fish and transferring to the new pond.

Discard the bag of water into the garden.

Do not mix it with the pond water.

No correct answer needed.

The standard method of acclimatizing sensitive fish safely.

Virtually stress free.

Just a recognized safe method of transferring your prized new fish.