Winter Temps and Feeding!

[barryian]

Here is my scenario. I'm ponding 25 years! 4 years ago, I rebuilt my pond to a fairly state of the art 2000 gallon pond.
All has been well but I was wondering something and the question will come at the end.

My pond is 2000 gallons. This might be redundant to some who know that in winter on Long Island, we can get quite cold.
Since the rebuild, in winter I have a 1000 watt deicer directly in from of my skimmer. I built a digital temperature control panel that the deicer is plugged into in my shed. The temps are set to go on at 34F and off at 37F ...
The pond being 4 feet deep gets some earth warmth, correct. So all filtration, bio, uv's are naturally drained and blown out.
The skimmer is all that is working with the deicer.

With this scenario, my water temp at worst dropped to 47F at the worst days with a cold snap of about 12F for a low and 20F for a high. This said, the temps stayed at 47F .... As my high temp as today, the pond reached 52F ....

And so the question: Being my pond somehow with this setup maintains a high steady temp, my koi aren't in much of
a hibernation state as a 35-40F pond. I believe if I fed them once a week, they would digest, just slowly like over 3 days. The skimmer filter and biofilm are still woking at this temp, correct or incorrect?

So am I hurting the koi by not ever feeding a small amount of food during this 50F temp? or ... would I do more damage by feeding them some pure protein free food here and there during a warm spell?

All has been well each year, no fish loss, no disease. Obviously if it's not broken, don't fix it but just looking for opinions.

Thanks all !!!!

 

[Meyer Jordan]

All are already aware of my response to this neverending question.......If your fish appear hungry, feed them. Only feed proportionate to the water temps. Low temp---less, warm temp---more, Also studies have shown that it really makes no difference whether the food is high protein or not.
I will be happy to elaborate if requested.

 

[barryian]

All are already aware of my response to this neverending question.......If your fish appear hungry, feed them. Only feed proportionate to the water temps. Low temp---less, warm temp---more, Also studies have shown that it really makes no difference whether the food is high protein or not.
I will be happy to elaborate if requested.

@Meyer Jordan ... How are you Meyer? Hope all is well! Today, my koi were swimming around the surface or just under it as if I came to feed them. You don't think a light occasional feeding would be detrimental if they are eating in 50F temps? I've always started and end the seasonal titrating to an eventual no protein food to make digestion easier, especially in cooler waters. Since when does protein not matter?
Theoretically, once in a week shouldn't affect the ammonia level as the biofilm + skimmer running with a pad should be effective for such small amounts of food, wouldn't you agree? Thanks for your input.

 

[Tula]

This is my first winter covering my pond and it's been unseasonably warm...go figure ! Anyway, I'm not feeding, but notice water celery is growing, so I figure they can nibble on it.

 

[Meyer Jordan]

@Meyer Jordan ... How are you Meyer? Hope all is well! Today, my koi were swimming around the surface or just under it as if I came to feed them. You don't think a light occasional feeding would be detrimental if they are eating in 50F temps? I've always started and end the seasonal titrating to an eventual no protein food to make digestion easier, especially in cooler waters. Since when does protein not matter?
Theoretically, once in a week shouldn't affect the ammonia level as the biofilm + skimmer running with a pad should be effective for such small amounts of food, wouldn't you agree? Thanks for your input.

Let me address a couple of points here.

Feeding-
Below is a direct quote from just one of the many documents that verify low temperature feeding in common carp (Koi).
"At 6°C, though both adult and youth would still feed, the feeding quantities were only 0.01% and 0.35% of body mass. Daily feeding rate of adult and youth reached 1.21% and 2.63% at 14°C, respectively. Both adult and youth carps reached the maximum daily feeding rate at 28°C, being 2.84% and 12.06% of body mass, respectively. The daily feeding rate of adult and youth reduced suddenly after at 34°C, and the daily feeding rate was only 0.74% and 9.45%
of body mass, respectively."
Effect of Water Temperature on Feeding Rhythm in Common Carp
Chen Song-bo, Chen Wei-xing, Fan Zhao-ting
From this it can be seen that, although the demand for food is a tiny fraction of the maximum rate, a demand for food does exist even at very low water temperatures.

Ammonia-
Ammonia can only be considered as an indirect result of feeding in that Ammonia is a by-product of fish respiration and an increased respiration rate is a direct result of feeding. Of more importance is the relation of the respiration rate to temperature. Below is a graph of this relationship.

As evidenced by this chart, at a water temperature of 10C the respiration rate is already more than 50% of the rate seen at typical Summer pond temperatures. This means that Ammonia production is over 50% of the maximum expected under normal conditions. Will a water quality problem arise with supplemental biofiltration off-line? Only close monitoring will answer that question and some hard decisions on the appropriate course of action. It is at times like these that fish load truly becomes a critical issue.

 

[barryian]

Let me address a couple of points here.

Feeding-
Below is a direct quote from just one of the many documents that verify low temperature feeding in common carp (Koi).
"At 6°C, though both adult and youth would still feed, the feeding quantities were only 0.01% and 0.35% of body mass. Daily feeding rate of adult and youth reached 1.21% and 2.63% at 14°C, respectively. Both adult and youth carps reached the maximum daily feeding rate at 28°C, being 2.84% and 12.06% of body mass, respectively. The daily feeding rate of adult and youth reduced suddenly after at 34°C, and the daily feeding rate was only 0.74% and 9.45%
of body mass, respectively."
Effect of Water Temperature on Feeding Rhythm in Common Carp
Chen Song-bo, Chen Wei-xing, Fan Zhao-ting
From this it can be seen that, although the demand for food is a tiny fraction of the maximum rate, a demand for food does exist even at very low water temperatures.

Ammonia-
Ammonia can only be considered as an indirect result of feeding in that Ammonia is a by-product of fish respiration and an increased respiration rate is a direct result of feeding. Of more importance is the relation of the respiration rate to temperature. Below is a graph of this relationship.
View attachment 97000
As evidenced by this chart, at a water temperature of 10C the respiration rate is already more than 50% of the rate seen at typical Summer pond temperatures. This means that Ammonia production is over 50% of the maximum expected under normal conditions. Will a water quality problem arise with supplemental biofiltration off-line? Only close monitoring will answer that question and some hard decisions on the appropriate course of action. It is at times like these that fish load truly becomes a critical issue.

Hmm - Doesn't address my current thoughts.
When it comes to feeding at anytime of year, I never know the amount of food weight in regard to fish weight. For 25 years, it's been nothing but a guess, if even that .... it comes down to just feeding my fish and assuming they ate enough because they finish and they're less interested 10 minutes later.
Sounds very shallow but koi feeding has always been a mystery to me.

 

[Faebinder]

I don't believe you are harming them by not feeding them if temp is below 50 in the pond. Feed at 50. If they are hungry they will the algae around them... they don't need a lot survive. Don't overestimate.

On the other hand if you decided to feed and temperature is under 50 and they decide to eat then I bet you won't need much per fish.

 

[Meyer Jordan]

I don't believe you are harming them by not feeding them if temp is below 50 in the pond. Feed at 50. If they are hungry they will the algae around them... they don't need a lot survive. Don't
overestimate.

A valid argument, but the other side of the coin should be given consideration. If, because supplemental feeding is withheld, the fish must utilize energy stores just to maintain basic bodily functions, the fish as a whole and its immune system in particular will be weakened thus opening it up to myriad pathogenic attacks that it is unable to fend off when weather moderates.
I suspect that more fish are lost in the Spring because of being underfed during the Winter than any other cause.

 

[barryian]

A valid argument, but the other side of the coin should be given consideration. If, because supplemental feeding is withheld, the fish must utilize energy stores just to maintain basic bodily functions, the fish as a whole and its immune system in particular will be weakened thus opening it up to myriad pathogenic attacks that it is unable to fend off when weather moderates.
I suspect that more fish are lost in the Spring because of being underfed during the Winter than any other cause.

Now that puts some light on the answer I was looking for. Thanks....

 

[barryian]

A valid argument, but the other side of the coin should be given consideration. If, because supplemental feeding is withheld, the fish must utilize energy stores just to maintain basic bodily functions, the fish as a whole and its immune system in particular will be weakened thus opening it up to myriad pathogenic attacks that it is unable to fend off when weather moderates.
I suspect that more fish are lost in the Spring because of being underfed during the Winter than any other cause.

Hi Meyer - I just received the email and seeing this section as one of the highlights. So, it got me back to re-read. I am I understanding this correctly. By feeding them very small amounts here and there @ 50F will start their system going more so opening them up to problems or the just the opposite?

 

[Meyer Jordan]

Hi Meyer - I just received the email and seeing this section as one of the highlights. So, it got me back to re-read. I am I understanding this correctly. By feeding them very small amounts here and there @ 50F will start their system going more so opening them up to problems or the just the opposite?

Feeding fish does not "start their system going more" only rising temperatures will accomplish that. Providing the nutrients required for maintaining a current metabolic rate is only logical. Keep in mind that this metabolic rate also directly influences the functioning of the fish's immune system. The ability of fish to fight off pathogens is already severely reduced at lower temperatures. If a fish must rely on stored energy to maintain even a low metabolic rate this further weakens the immune system. Fortunately aquatic pathogens are, for the most part, also less active at lower temperatures but it is with the warming that comes in Spring that issues begin to manifest. If a fish has been further weakened by limited nutrient intake (fasting or starvation), their immune system will be slow to respond to the rising temperatures. This is when they are most susceptible to disease, infection and parasitism. "Aeromonas Alley" ring a bell.

 

[barryian]

Feeding fish does not "start their system more". Providing the nutrients req

Well then, if their swimming, not huddled and it's mild the next few days, we'll have to test their appetites!

 

[MitchM]

I think I would feed my fish during the winter, if they were accessible.
My ice cover is too thick, hence one reason I prefer to try and keep a more complete "ecosystem" pond.

 

[barryian]

I think I would feed my fish during the winter, if they were accessible.
My ice cover is too thick, hence one reason I prefer to try and keep a more complete "ecosystem" pond.

Well, my pond defies all physics but never had 1 gallon of 2000 freeze and we get cold. I think you did those formulas Mitch, correct
back some time? So, yesterday, 27F during the evening, 40F ish during the day and running through the deicer when on, this pond stays
at 50F.
I fed them a mix, not much yesterday. I'd say their energy level was 10 fold. They were cruising the surface as if it were summer for a good part of the day. I wouldn't do that often with only the skimmer filtering through the main drain to the falls, no bio on, but possibly once in a week. I would
think if I hadn't eaten in 2-1/2 months, I'd be energized too ...lol .... just have to watch those ammonia levels. probably not from once a week.
Never really tried that in 25 years.

 

[mrtrumpet]

I am not running my pump/filter this winter, but have noticed my fish are a little hungry too. They are grazing around the rocks on warmer days and only at the bottom when it's very cold. With the warmer temps this winter it seems there may enough in my pond to keep them satisfied.

My question is this: Since I am not running any filtration would it be best to not feed them and chance an increase in amonia? Or will the lack of filtration not be a problem if I do give them a little food?