Michigan winter = alot of fish death

[max384]

You can't use a chemical to help with ammonia. What are your ammonia, nitrite, and nitrate levels?

The dechlor I use is also advertised to reduce ammonia levels. I've never had a problem with ammonia, so I can't vouch for its efficacy, but it's advertised as such.

 

[max384]

This was the worst winter in PA that I've ever witnessed. We broke many, many records this year... and my pond suffered big time. I had 7 larger shubunkins (6-12") and about a dozen fry that showed up last year. Six of the seven shubunkins died and I've seen about 6-8 of the fry. I've always left the waterfall running throughout the winter with great results. However, this year the waterfall froze up. I made the mistake of just letting the pond freeze over and get to it in the spring. The results were obviously very poor. This is the first time I've ever had ANY fish die on me over winter.

I don't want this to happen again, so I decided to upgrade the pond. My current pond is 300-400 gallons at about 2 feet deep. My new one is 3.5 feet deep and about 2000 gallons. I'm also installing a bottom drain this time around. I'm planning on doing something to warm the water coming out of the waterfall next winter, though I don't have a solid plan on what I'm doing. Worst case I'll use an oxygen stone and a heater.

 

[Tula]

I'm thankful I re homed over 50 shubunkin and comet last fall, or surely I'd have had fish loss. I have an area of my pond that is close to 4 feet deep, and there is a large flat rock over it, which is where my five koi huddled most of the winter. There wouldn't have been room for them and all the others. It was a very hard winter.

 

[dieselplower]

The dechlor I use is also advertised to reduce ammonia levels. I've never had a problem with ammonia, so I can't vouch for its efficacy, but it's advertised as such.

Some of them do detoxify ammonia for about 24 hours.

 

[koshki]

This was our first winter with my "glorified birdbath", and it turned out to be a doozy.

My nine little goldfish huddled in the bottom of the skimmer near the pump, and under the pond heater we stuck in there. The waterfall continued to run almost the entire winter, even when there was a crust of ice over it nearly the entire winter. Finally, during the last really cold snap we had, the falls froze up completely.

All nine made it to the big thaw. Unfortunately, I think one of them (of course, my favorite) became lunch for a marauding raccoon. No green cover for those little guys at the moment.

We are now redoing this whole thing, making it deeper and adding a bog. It will still be small (maybe around 400 gallons), but definitely a better environment for the fish.

 

[snoozer]

I am new here but also lost many fish this winter. I lost 9 koi, of course they were the nicest ones that died and probably 30 gold fish. I kept 2 pumps bubbling to keep openings in the ice along with my home made floating deicer. I ran two air pumps as well. I think the die off has come to an end finally, no more floaters for the last few days. Definitely survival of the fittest this year.

 

[Waterbug]

I don't normally put any chemicals in my pond but thinking of adding some chemical to help with ammonia and perhaps reduce sludge build up. Will this stuff work in a lined pond?

The sludge reduction stuff is a scam. The ammonia binders work but they're sure not a long term solution. It is better imo to learn about ammonia before fixing stuff that doesn't need fixing. For sure you don't want to be fixing ammonia before testing the level. The ammonia test you use will probably say "Total Ammonia". Ammonia changes between 2 forms depending on water temp and pH. It's kind of a chemical reaction. As water gets colder more toxic ammonia changes into non-toxic form. As it warms the ammonia changes into the more toxic form. So a test result for Total Ammonia only tells you part of the story. With water temp and pH you can look up the toxic amount at this web site.

This is really important in the spring because the water is too cold for algae to start growing and sucking up ammonia and too cold for ammonia converting bacteria to really get going. So there can be ammonia present. But the water is cold so the ammonia level may not be very harmful. Some people see the Total Ammonia number and panic. Start tossing in all kinds of stuff, doing dangerous water changes. All with fish having barely making it thru the winter, low immune system and no problem is turned into a big problem.

Also, during winter, I use a small pump as a bubbler to keep a small opening within the pond. I was also told to run a stock heater that farmers use for cattle/horse troughs. Will this help or hurt?

Impossible to say. Keeping an opening can help with gas exchange but the downside is water is made much colder. The question that's impossible to answer is which is the greater risk? The longer a pond stays ice covered the the higher the risk of poor gas exchange. But if the air is really cold for a long time and there's a opening in the pond moving water around the higher the risk fish will succumb to cold. Fish can survive a long time in both cases, but there are limits.

Keeping a pond clean going into winter lowers the gas exchange risk. The bigger the pond (gals wise) the lower the gas exchange risk. The deeper the pond the lower the risk of cold.

Over the years I've read a fair amount from pond keepers in places like Sweden. I grew up and kept ponds in Upstate NY and know about cold winters, but these dudes have a much longer periods of cold. Ponds ice over for months. They generally don't keep an opening in ice and they have pretty big fish loads. They do certainly lose fish, but not every year. It makes me think people in the US are going a little crazy with the whole opening in ice thing and not understanding the dangers of cold water. I've been reading forums for more than 20 years and it's only in the past say 5 years has this universal advice of keeping ice open has been standard fair in pond forums, less so in the more serious Koi forums. I think people are being misled by advice being repeated with very little understanding. There are a lot of "experts" telling people to keep openings but they never ever actually test anything.

Heaters don't raise the temp of the water at all, they just barely raise the temp around them enough to keep a small opening. It's the same problem as the bubblers, makes water colder.

Most people know warmer water rises, but that's not actually completely true. 39F water is the heaviest water so 38,27,36,25,34,33,32F water rises while 39F sinks. So colder water rises above warmer water. But this only happens well if the water is very calm, like under ice. This is why wild fish can survive in cold climates and also why ice forms on the top of water rather than at the bottom. Key word is "forms", that ice floats is another matter.

Even wind can be enough to mix water so the entire body drops below 39F. The fish have no place to go to stay "warm". Bubblers and heaters can certainly mix the water. The longer fish have to be in sub 39F water the harder it is on them. Being only 3' deep makes the problem even worst than say 4 or 5' deep.

 

[alahoop]

I am new here, and also from Michigan. We lost most of our fish over the winter. Four of our smaller goldfish survived (though the difference in size is only an inch or two), and we lost about 12 fish. We keep an airstone running through the winter, and have only been doing this for a few years, but haven't lost any fish during previous winters. A neighbor who keeps koi told me he lost all but one of his (not sure of his pond size, so overstocking may have been an issue there. It definitely wasn't in ours though).

It was exceptionally cold here last winter, but I know that people in colder climates keep fish, so I have been wondering what the difference is. Our pond is just under 3" deep at its deepest.

My husband works with a man who said that his in-laws live on a small lake, and they saw tons of dead bluegill when they visited. His father-in-law said it was the worst he'd ever seen it, so it wasn't just an issue for those of us with smaller ponds.

 

[brokensword]

alahoop:

did you have the airstone near the pond bottom or suspended near the surface? In another thread, I report that at another site, they found that keeping the airstone low caused problems in that the water mixes, disturbing any stratification (water below 39 deg sinks as it's more dense and that means the colder water is at the top, hence ice forms there). Too much air can do the same thing. Does you pond have a lot of decaying plant matter? That too can cause issues, though keeping a hole open helps alleviate the potential issues.

Also noted; a couple of years ago, the large 'pond' nearby froze over for such a long length of time that when spring finally arrived, hundreds of fish floated to shore, killed by one of the issues noted above; not enough oxygen, too much toxic gas buildup, water supercooled (though prob not with a natural pond as there was no air input). This year, after the worst winter I can ever remember, there were no dead fish at all, and I'd definitely say the conditions were twice as bad as the winter noted previously. So I'm making an assumption that the earlier kill thinned out the population enough so that though conditions were worse this year, the amount of oxygen needed was a lot less and so, there was no fish kill--THIS YEAR.

For me, I lost 5 of about a hundred fish, two 4" and three 2" versions, while using just an airstone as yourself. I have about 2800 gal in my pond, 4' max depth, did not remove the snow, had about 8" of ice (approx), and have a fairly low supply of decaying plant matter to deal with. Just to give you some comparison. And, I don't necessarily think the bad winter killed my fish as much as they were probably weaker parts of the whole, as I did not lose very many at all. Certainly they were young fish as the larger 8" fish all came through well, looking fat and healthy when the ice finally did melt.

 

[Waterbug]

The issue with whether toxic gases build to deadly levels has to do with fish load and rotting organic matter (volume and type) and not very related to temp other than the length of time the water is ice covered. But really it's also a problem in summer too. A clean pond going into winter greatly reduces the risk of gas issues.

 

[alahoop]

brokensword,

We keep the bubbler near the surface. It's hooked to a styrofoam "donut" to keep it from sinking too low.

As for the decaying matter, there was more of it this year than in years past. Our ponds are both under trees, and cleaning them out is a daily task in the fall. It got cold and froze over so quickly that I think we just didn't get everything out. That may have been a factor. It's hard to tell what was already in there, and what fell/blew in as the ice melted.

One thing we noticed was that many of the fish were frozen in the ice. I think this probably implies that they died early in the winter? I don't think they died from freezing in the ice, or anything, but they obviously had time to float to the top and freeze there. The bodies were mostly fairly well preserved, and while we didn't look them over that closely, we didn't notice any obvious signs of anything. I don't think it was disease that killed them though, I also think it had something to do with the oxygen levels in the water (especially because it was the smaller fish that survived).

 

[Waterbug]

Depends on the climate, but in NY we went thru many thaw/freeze periods. So I'd see stuff in the ice from time to time.

 

[callingcolleen1]

Sorry to hear of your dead fish.

I have had my fish outside for over twenty three years and have no trouble in the minus 40 below here in Canada. I would never trust or use a air stone or bubbler. My pond set up is different than most, and I do everything pretty much different than most.
I have only very big pre- pump filters that are all under water, this way they tend not to freeze.
I never shut down the main flow, that keeps all three connecting ponds circulating. The main pumps runs and the extra summer pumps are put away, like spitter, and no big splashing waterfall, just water ways that keep the three ponds circulating as one pond.
The running water all winter keeps the top ponds from freezing as hard, although I still can get lots of ice, despite the use of a big heater floating where the water moves well.
I check my ponds every day in the extreme cold, some times several times a day during the most extreme temperatures of minus 40 below. Then If that is not enough, I also peek out the window in the bathroom several times a day during the coldest weather too. I also top the bottom pond every day when extremely cold, to make sure it will have lots of water to keep the system flowing, as water gets displaced and turned into ice on the top ponds. I have spare hose in house and run it out the window to top up ponds during the coldest months.

Large koi need clean running water all winter, so why does everybody put the filters away in the winter? Ice cold water does not always equate to crystal clean clear water, that is why I leave my underwater pumps and filters run all winter. Get a good pre pump underwater filter to keep the water fresh, that will be big enough to run all winter without clogging up. and enough of a current to keep with water fresh. Ice also melts away much quicker if the water is running all winter, and ice will not get as thick either.

Last but not least, get a good floating heater, I have a 1250 Watt that I used most of this year, and I switch to the 1500 watt floating cattle heater when below minus 30 or so degrees. Place the heater where the water moves well, so the water is evenly heated.

Keep a watchfull eye out all winter, ensure that the pond is moving and that there is lots of water below the ice.
That is my best advice and good luck in the future. I am sure you will figure out a way that will work good for you as you gain more experience too.

 

[Dave 54]

brokensword,

We keep the bubbler near the surface. It's hooked to a styrofoam "donut" to keep it from sinking too low.

As for the decaying matter, there was more of it this year than in years past. Our ponds are both under trees, and cleaning them out is a daily task in the fall. It got cold and froze over so quickly that I think we just didn't get everything out. That may have been a factor. It's hard to tell what was already in there, and what fell/blew in as the ice melted.

One thing we noticed was that many of the fish were frozen in the ice. I think this probably implies that they died early in the winter? I don't think they died from freezing in the ice, or anything, but they obviously had time to float to the top and freeze there. The bodies were mostly fairly well preserved, and while we didn't look them over that closely, we didn't notice any obvious signs of anything. I don't think it was disease that killed them though, I also think it had something to do with the oxygen levels in the water (especially because it was the smaller fish that survived).

We koi keepers are serious about our winters and keep our ponds ice free throughout the winter months by either using aninline heater that fits into your pipe work and at 1KW upwards depending on the heater we keep the pond ice free however this has one flaw, the cost of running your heater 24/7
Others like ourselves have heavily insulated our ponds against the cold and have built a filter housing again insulated against the cold, then to top that off we use Policarbonate rofing sheet's that cover the pond until spring.
The net result is the Pond never goes bellow 7c even during a cold spell of -15c ...now you mentioned decaying matter "this doesnt help your fish and can work agaist them by killing them .
So we all clean our ponds of dead leaves detritus etc prior to winter in late fall you must also give your filters a good clean too.
The result f this gives them a fighting chance of getting through the winter in one piece, another thing we koi keepers do throughout the winter is water changes , to do this we use a method called the trickle method via a dechlorination unit , the temperature of the pond helps warm the water as it trickles back into the pond , if done correctly you may not loose any heat or just .1c.
We again clean our filters in late spring and again in mid summer the net result of this is that all our koi come safely through the winter wih no harm which is important as spring can be a bitch what with the Areomonas bacteria and others attacking your fish they need to be as strong as possible to withstand these attacks and thus get through in one piece

Dave

 

[Tula]

Sorry to hear of your dead fish.

I have had my fish outside for over twenty three years and have no trouble in the minus 40 below here in Canada. I would never trust or use a air stone or bubbler. My pond set up is different than most, and I do everything pretty much different than most.
I have only very big pre- pump filters that are all under water, this way they tend not to freeze.
I never shut down the main flow, that keeps all three connecting ponds circulating. The main pumps runs and the extra summer pumps are put away, like spitter, and no big splashing waterfall, just water ways that keep the three ponds circulating as one pond.
The running water all winter keeps the top ponds from freezing as hard, although I still can get lots of ice, despite the use of a big heater floating where the water moves well.
I check my ponds every day in the extreme cold, some times several times a day during the most extreme temperatures of minus 40 below. Then If that is not enough, I also peek out the window in the bathroom several times a day during the coldest weather too. I also top the bottom pond every day when extremely cold, to make sure it will have lots of water to keep the system flowing, as water gets displaced and turned into ice on the top ponds. I have spare hose in house and run it out the window to top up ponds during the coldest months.

Large koi need clean running water all winter, so why does everybody put the filters away in the winter? Ice cold water does not always equate to crystal clean clear water, that is why I leave my underwater pumps and filters run all winter. Get a good pre pump underwater filter to keep the water fresh, that will be big enough to run all winter without clogging up. and enough of a current to keep with water fresh. Ice also melts away much quicker if the water is running all winter, and ice will not get as thick either.

Last but not least, get a good floating heater, I have a 1250 Watt that I used most of this year, and I switch to the 1500 watt floating cattle heater when below minus 30 or so degrees. Place the heater where the water moves well, so the water is evenly heated.

Keep a watchfull eye out all winter, ensure that the pond is moving and that there is lots of water below the ice.
That is my best advice and good luck in the future. I am sure you will figure out a way that will work good for you as you gain more experience too.

Collen,
What type of filter do you run during the winter? Mine is an above ground pressurized type, so I have to put it away, but am interested in ideas to filter my water in the winter. Thanks!