Water Temperature difference

[cas]

How about those solar covers they put on swimming pools to keep the water warm?
Here is a 4x8 for $19.99 ......
https://www.solarcovers.com/product...gular-12-mil?gclid=CIuT9PObjtQCFZ61wAodioULEQ

 

[mrsclem]

How about not completely filling the new pond? a smaller amount of water will warm up faster and then just add more each day till its filled.

 

[Meyer Jordan]

Water temperature always lags behind air temperature because it does not change that quickly naturally. Fish are genetically predisposed to adjust slowly to temperature changes based on this. In fish transfer, the greater the temperature difference between the two (2) containers of water the longer it will take for fish to adjust. In major temperature differences, this sudden change will induce thermal shock in fish. They may or may not recover depending on the size of this temperature differential. They will certainly be subjected to additional stress over and above the stress induced by the actual physical transfer, which is considered the Number 1 stressor in fish.
Floating a bag or container on the water surface of a pond for a few minutes truly accomplishes nothing. The fish will be subject to greater stress remaining in the bag or container.
Reaction to the stress induced by such a temperature change may be from the fish heading to the bottom of the pond to immediately going belly-up.

 

[EricV]

Just let the pond water sit for a few days and it will come to some sort of equilibrium. It still might not come up to 80 degrees since it will be in contact with the ground, which should be cooler. But it will be closer.

 

[Gordo33]

Thanks for all the great advice. I have two small pumps that I will set up as suggested by @MitchM and hope to create an equilibrium between the pond and temporary pond.

 

[Gordo33]

So I just checked he temporary pond and the water temp is 59 degrees. I let the outside spigot run for a few minutes and the water coming out is 57 degrees. Looks like fish transfer will occur early in the morning.
Now if it would just STOP raining here so I can drop the liner in

 

[Gordo33]

Fish are genetically predisposed to adjust slowly to temperature changes

Even with a 30 degree change up and back down in the same day. At least this is what I have observed in the temporary pond. A couple of weeks ago we had 3 90-92 degree days, with nights dropping down into the upper 50's to low 60's. I kept a close on on the fish and there was no change in behavior or loss.

 

[Meyer Jordan]

Even with a 30 degree change up and back down in the same day. At least this is what I have observed in the temporary pond. A couple of weeks ago we had 3 90-92 degree days, with nights dropping down into the upper 50's to low 60's. I kept a close on on the fish and there was no change in behavior or loss.

These were air temperatures, right? Water temperatures do not fluctuate that wildly within a 24 hour period naturally. Partially because the energy exchange in water is slower than in air and also ground temperatures are a major factor in water temperatures.

 

[Gordo33]

These were air temperatures, right? Water temperatures do not fluctuate that wildly within a 24 hour period naturally. Partially because the energy exchange in water is slower than in air and also ground temperatures are a major factor in water temperatures.

Yes , but the temporary pond'swhich is at most 250 gal,, water temperature is staying within 4-6 degrees of the air temperature. I was monitoring the water today and this what I found
Air temp for today's high 72 degrees water temp 67 degrees. I just took a reading and the air temp is 66 degrees and the water temp is 62 degree. So maybe because the volume of water is small the temporary pond water temperature is moving with the air temperature. During the mini heat wave we had a couple of weeks ago when I got home from work the air temp was 92 degrees and the pond temp was 86 degrees. That evening the air temp dropped into the mid 70's and the water temp was in the low 70's.

 

[Meyer Jordan]

Yes , but the temporary pond'swhich is at most 250 gal,, water temperature is staying within 4-6 degrees of the air temperature. I was monitoring the water today and this what I found
Air temp for today's high 72 degrees water temp 67 degrees. I just took a reading and the air temp is 66 degrees and the water temp is 62 degree. So maybe because the volume of water is small the temporary pond water temperature is moving with the air temperature. During the mini heat wave we had a couple of weeks ago when I got home from work the air temp was 92 degrees and the pond temp was 86 degrees. That evening the air temp dropped into the mid 70's and the water temp was in the low 70's.

That is correct: the smaller the body of water (gallons) the faster it will follow changes in air temperatures, in addition, the shallower a body of water the faster it will follow air temperature changes.
This is why it is important to monitor the water temperature of both the pond and the temporary holding tank, making the fish transfer at the optimum time when the water temperature of both are closest.
The fish are not affected by this faster change in water temperature in the holding tank because even though it may exceed 5 degrees F, the change is over a period of hours. It is the abrupt change in temperature that can and usually does cause the most problems.

 

[AlyssaFish]

Perhaps you can cool the temporary pond at the same time as the other is warming up? Perhaps do small water changes every hour for a day?

 

[Gordo33]

Perhaps you can cool the temporary pond at the same time as the other is warming up? Perhaps do small water changes every hour for a day?

thanks for input. i resolved what i thought was going to be a large temp difference by monitoring the early morming and evening temps. They are running within the 5 degrees recommended for safe fish transfer. With air temps running 5-7 degrees below average as opposed to the mini heat wave we experienced several weeks ago the temporary pond/pool temperature has not exceeded 72 degrees. during the 3-4 day heat wave the temporary pond was hitting 85-88 degrees.