Feeding Temp Question?

[Meyer Jordan]

Perhaps it may be of interest as to what the leading Japanese Koi food manufacturer has to say. Makes sense to me considering most sites other than forums and Koi Clubs agree with this chart.
http://www.hikari.info/topics/to_06

One study-
Overwintering of farmed common carp (Cyprinus carpio L.) in the ponds of a central European
aquaculture facility—measurement of activity by radio telemetry
Christian Bauera,*, Gqnther Schlottb
- documented grazing activity at 3.1C.

 

[Dave 54]

Perhaps it may be of interest as to what the leading Japanese Koi food manufacturer has to say. Makes sense to me considering most sites other than forums and Koi Clubs agree with this chart.
http://www.hikari.info/topics/to_06

One study-
Overwintering of farmed common carp (Cyprinus carpio L.) in the ponds of a central European
aquaculture facility—measurement of activity by radio telemetry
Christian Bauera,*, Gqnther Schlottb
- documented grazing activity at 3.1C.

There has always been a 10c cut off point in our clubs winter preperations , I for one do it as does everyone I know .
Yes the Japanese and other feed companies may have formulated for eating down to 5c but I dont know of anyone who would feed to 5c .
Yet even the company states at 10c "When the water temperature is in this range, technically you may stop feeding until spring" but then goes on too say. "If your koi are active and you want you can feed an amount they will consume within a minute or so,[not the normal 5 minutes they normally qoute].
Koi fed up during the spring summer and early Autumn do not need to be fed bellow 10c
They should as the temperatures drops have been fed a wheatgerm and garlic mix prior to this from mid autumn down to 10c .
Personally I think its down to the fish keepers own judgement as to when they stop feeding just as it is their judgement as to when in the spring they start feeding again.
We normally say if the temperature has been stable at above 10c for two weeks or more, then its safe to start again but with a wheatgerm and Garlic mix not a heavy protien pellet, they are reserved for late spring through to mid autumn.

Dave

 

[Dave 54]

I have gotten generally the same message from random articles on here about not feeding Koi at a low temp but I need to know what is that temp and also if the temp stays that low for a long period then won't the fish starve ?

Marshall if you followed a high protien koi food diet during the summer and fed them at the correct rate of feed throughout .
Swopping your feed to the wheatgerm and garlic "mid Autumn", then you shouldnt have any worries about your koi starving ..
They are perfectly capable of looking after themselves during the winter months .
They enter into a torpid state at 5c downwards, at 2c they are nearer to death than alive , on warmer days they will come out of this state .
Then should they feel a tad peckish during this time they will then normally crop the algae that we promote the growth of in summer along the sides and bottom of the pond] as the temperature goes back down they will go into a torpid state again.
We monitor the koi for any signs of stress during this dangerous time and can apply heat to the system by warming the filter housing if need be .
We also do a reduced Maintenance regiem during this time and do water changes on a bi-monthly basis through out the winter on a trickle basis , using the ambient temperature of the pond to warm the water trickling in to the pond .

Dave

 

[Smaug]

Maybe a bit of a hijack but I'm sure the op would be interested as well. Just how cold for how long do the air temps have to be to drop the temp of a 3 ft deep pond below 2c? I have never checked the water temps in the dead of winter. I have also never lost any fish to the winter either so I assume I'm not going below that 2 deg c mark.

 

[Dave 54]

Maybe a bit of a hijack but I'm sure the op would be interested as well. Just how cold for how long do the air temps have to be to drop the temp of a 3 ft deep pond below 2c? I have never checked the water temps in the dead of winter. I have also never lost any fish to the winter either so I assume I'm not going below that 2 deg c mark.

Sorry Smaug I cant truthfully answer that its maybe one for you to answer?
You see as from late autumn onwards we cover our pond with policarbonate roofing sheets.
The pond itself is free standing and both it and the filter housing are insulated as are all the pipres.
The housing itself itself having policarbonate roofing sheets also.
The net result is that even at -15c our pond will not go bellow a temperature of 7c , which on sunny days will raise up to 9.
However we do monitor both the outside air and water temperatures in the pond so at a quick glance to the right and at this moment in time was have an air temperature of 12.9c , with the pond water temperature running above that at a pond at 14.4c




Dave

 

[Smaug]

I'll get a remote thermometer and check it out.

 

[Dave 54]

Well worth the investment if you can get the right pond/pool thermemter the one we bought was a german make the
TFA 30.3053.IT Malibu Wireless Pool Thermometer check them out on Amazon UK well worth a buy .
Good Germanm engineering

DAve

 

[Smaug]

https://www.google.com/url?sa=t&sou...C2_s8Th8QJ1WKEUig&sig2=k-rDuqBgyt8fCCDGaJ193Q

Thanks. I'll order one

 

[Marshall]

Caveats overdue:
I have already solved this issue by going ahead and switching on my heat system which keeps the water at a minimum of 55F so no worries.

 

[Smaug]

Caveats overdue:
I have already solved this issue by going ahead and switching on my heat system which keeps the water at a minimum of 55F so no worries.

Won't that be very expensive?

 

[Meyer Jordan]

Maybe a bit of a hijack but I'm sure the op would be interested as well. Just how cold for how long do the air temps have to be to drop the temp of a 3 ft deep pond below 2c? I have never checked the water temps in the dead of winter. I have also never lost any fish to the winter either so I assume I'm not going below that 2 deg c mark.

The average depth of the frost line for a location will greatly influence this. The rule of thumb as suggested by the AKCA is that the depth of a pond should be at minimum twice the depth of the frost line. This supposedly will insure that bottom temps will not drop below 39F.
The water temperature of in-ground ponds is controlled more by the ambient temperature of the surrounding soil than atmospheric temperature especially in the deepest area.

 

[Marshall]

Won't that be very expensive?

not really. It is a passive system that works much like a radiator heater only under water

 

[MitchM]

Maybe a bit of a hijack but I'm sure the op would be interested as well. Just how cold for how long do the air temps have to be to drop the temp of a 3 ft deep pond below 2c? I have never checked the water temps in the dead of winter. I have also never lost any fish to the winter either so I assume I'm not going below that 2 deg c mark.

Smaug, ambient temperature and pond water temperature are not directly correlated.
A pond's greatest source of heat loss is through evaporation.
High wind speed and low humidity, plus a low ambient temperature will cool off a pond dramatically.
My pond water temperature was 0.6 celcius / 33 farenheit this morning while the ambient temperature was -4 celcius / 24 farenheit.
All last winter, the lowest my water temperature dropped to was 1.7 celcius. The difference this year is that I'm trying to maintain open water for as long as possible. An ice cap will keep a pond warmer.
If you're interested in going through the exercise, have a look at the link in my signature below to calculate the heat loss for your own pond.

My pond is 5 feet deep and we have a 4 foot frost line.

.

 

[Smaug]

It's just one of those things I never really thought about because I've never had a problem with fish mortality. I'm aware of the factors that creates heat loss in a body of water,I asked the question more for an anecdotal response of someone's actual experiance. I do keep a thermometer in the water right up to when it starts to freeze,after that I never thought about it. Thanks for the info,I may try the math,,,,or more truthfully have my kid do it!

 

[MitchM]

I've never heard of cold water being fatal to koi or goldfish, any problems seem to be because of insufficient gas exchange.