cold weather consequences

[dick benbow]

Recently the Northwest experienced some super cold weather unlike any for almost a decade. Many new folks to the hobby were caught unawares and as a result had and will have problems.

Thought it might be a good idea to discuss complications as a result to weather
to help them prepare for next time and also what they may have to face healthwise this spring yet as a result.

Pipes were broken, power lost, ponds frozen completely over is one point of discussion...another might be the frostbite/injury because of the lower 30's temperature. Something as the koi start to increase metabolism in a month or so
that may adversely affect their health.

Grab a topic and share your experience/recommendations

[dick benbow]

Koi experience something akin to frostbite when the temps plummet and remain in place for any length of time. The damaged scales and skin are now subject to invasion by infection, causing loss of scales and flesh and creating an ugly red sore.

Things that contribute include leaves and dirt allowed to accumulate since the fall ( dirty conditions) and the presence of flukes and other paracites that are more than willing to take adsvantage of any situation. This generally takes place during the warming in March and april as the fish become active ( and so do all the bad guys)

After stress of what has just happened, to mess with the koi immediately is to add to their distress. Things like minor water changes and the addition of salt can help. (.03) But as the koi begin to act less stressed from the cold temps with the next warming session ( and temps begin to climb back out of the thirties and into the forties ) you can continue your cleaning of the pond
and if you don't know how to check for paracites get you KHA advisor to tell you what you need to deal with to treat for them. You'll have to check to make sure the water temps are high enough to make sure the medications will be effective. Now is also a good time as you have 4- 6 weeks to get a q tank upo and running if you do not have one. Medications and healing always respond better with higher temperatures. So many beginners do not know the gallonage of their pond so if you build a quaranteen tank be sure and meter it do that you'll make the proper administration of medication.
40's

[Arthur]

Excellent topic Dick.

This past weekend I have received many calls reporting koi in serious trouble. Here in the Potland area very windy conditions with temperatures as low as 17°F have caused pond temperatures to drop from around 47°F to as low as 29°F in a matter of days.

Yes, you read it right: pond water temperatures below freezing! This can happen in ponds with good circulation preventing ice formation and ice cold wind sweeping the surface.

Temperatures below 37°F cause extreme stress to koi as most of system functions shut down. Koi will no longer swim and some will lay down on their side.

Some people reported "saving" their fish by moving them to an indoor tank in warm water. Do not do that, you will kill the fish! At these low temperature, a koi fleeing the net will release adrenalin in their blood and because of the extreme cold their system will not be able to eliminate the adrenalin.

In addition, with water this cold, moving fish indoor (even into their pond water to start with) will raise their temperature too fast: 15-20°F in a matter of hours).

So what to do? Cover the pond to eliminate the cooling effect of the wind. A clear plastic tent/teepee will allow the temperature to come up as much as 10°F.

If you cannot place a cover over the pond, throttle down the water flow to almost a trickle and allow the pond to freeze over, maintaining an opening free of ice with a small surface heater. The water temperature under the ice can get up to 50°F in a pond deep enough (4'+).

When outside temperatures come back up to normal, slowly return the system to normal operation.

Like Dick said, observe the fish for frost bites and possible infection of these sites. But do not attempt to net and treat the fish until temperatures have come up some.

For what it's worth...

[jnorth]

Although I struggle with cold water every year there isn't much I can add to this discussion. However a friend of mine wrote a pretty good article on it. Here is a link to it http://mywebpages.comcast.net/recarlso/ click on "Winter Effects" on the left side of the page when you get there.

As for me, I move the prized koi inside for the winter in a 700 gallon qtank and do twice weekly water changes all winter. The rest of them tough it out in the cold . I plan to put a stop to this madness by building a new pond and putting a greenhouse over it.

[MikeM]

Dick & Arthur: I am sure some folks are going to be wondering about performing a prophylactic treatment with Proform-C or similar product as soon as the temperature is high enough. Normally not a good idea, in my opinion. But, I've no experience with the kind of cold you are talking about. Thoughts?

[dick benbow]

Jim with a last name like yours, I was hopeful you'd have something to say about the topic ( smile)

Thanks Arthur! You filled in a lot of gaps.....

[Birdman]

Good topic Dick, thanks for posting it.

[gofish]

Well, after finally getting the greenhouse done (better late than never) we just had the coldest air of the season. 4 above at night with windchills minus 15 and highs around 10-13 with lots of wind. The pond water stayed around 45 through all this cold weather. We had a solar cover over 80% of the pond before the greenhouse. The fish didn't seem to be nearly as active as they are right now. They actually seem to be begging for food. One of the biggest things you can do is get a greenhouse built.

Marc

[jnorth]

Quote: Originally Posted by dick benbow Jim with a last name like yours, I was hopeful you'd have something to say about the topic ( smile)

With a last name like mine you'd think I would like winter....but I assure you thats not the case .

Quick question on the salt though Dick...Wouldn't that lower the freezing temp on the water thus allowing the water (vapor) to get colder before freezing?

[Arthur]

Jim,

You are probably thinking of sea water (salted) not freezing as fast as fresh water (lake/pool).

The fact is that there is no salt in water vapor. Icing above above water occurs in the air (not the water). So in a pool/pond, salt will have little/no effect on freezing. The main reason why seas do not freeze as fast as pools is that the water moves (same as in pond with strong circulation reaching down to below 30°F without freezing).

I do not recommend salt in the pond in winter at any more than 0.1% as salt will cause erosion of the slime coat. This in turn will cause the fish to replenish the slime by using its protein reserve at a time when none is provided through food. This causes a snow ball effect robbing the fish of its winter reserves and weakening it for spring when the parasitic battle will happen.