Hey Lara. Believe me I understand how you felt at the sight of an empty or almost empty pond. Doing a rescue in subfreezing temps is a hoot. There are many good sites that can tell you all the details of putting the pond and the fishies to sleep for the winter. I'll just give you a brief overview after which I have no doubt there will be others to give even more info.
First, make sure the pond is very clean. No stray leaves or collection of mulm to give anerobic bacteria a place to grow. Cover the pond with netting to keep out leaves unless you have a very good skimmer. Next as temps drop, change the food to an Autumn recipe. It is easier for the fishies to digest. Test all the water perameters so you know the water itself is good. As temperatures drop and the water is consistantly 50oF or less, stop feeding the fish. When ice starts to cover the pond, pull the pump and store it in a cool, dry location unless you have one of the older oil filled pumps. If you do then it should be stored in a bucket of water to prevent the seals from deteriorating. Bacteria in the biofilter will be mostly inactive below 45oF so you may want to drain a skippy or similar setup to prevent cracking the container. In zone 5, we will get several inches of ice. An air bubbler won't do the job of keeping a hole in the ice for long. I have a 100 watt deicer that would likely keep enough of a hole open but I get nervous and float a homemade deicer. Two 60 watt bulbs will keep a large hole open. A typical design is in the link. Greg Bickal has a lot of good designs. There is a difference between a pond heater and a deicer. A heater uses a great deal of electricity and tries to keep the whole pond warm. 1000 gallons is a bit big to try that. A deicer only keeps a small area open which is enough for gas exchange so toxic gasses don't build up in the water. If the water is clean and you are not dropping food into the water and there is at least a small hole in the ice, the water will not get stagnant because most bacterial action has stopped or is greatly reduced. The bubbler is a safety device that helps keep oxygen levels up. If you use a bubbler, keep it close to the edge of the pond and cover it and the tubing so it doesn't get blocked by the moisture in the tubing freezing. Say nighty night to the fish, who will be dozing on the bottom by this time. Sandy

Here is a link that might be useful: Greg's info

Thank you very much! I've been pulling out leaves, presumably I should take out the sub-surface floater plants as well? I assume they will die when temps get too low. Also, how do I clean out mulm? I don't think the bottom of the pond is particularly littered, but my pond liner is black so I'm unsure. Also, my deep end is 4 ish feet down; I don't know that I could get a vacuuming device down there. Will a very fine mesh net do it?
I've pretty much stopped feeding already, as they seem uninterested, but I will check my temp and water quality tomorrow.
Thanks again. I will continue to check back for hints - I really value this forum.

Lara

Lara, if I may add to Sandy's good information.
If your pump is the magnetic type and you decide to take it out of the pond to store it or not, it should be taken apart at the end of the pond season and cleaned out.

Cleaning the pump's impeller and rotor to remove the gunk that has accumulated in there over the summer is advised by the pump manufacturers.

This gunk can set up like glue over the winter and can/will inhibit the pump's impeller/rotor from rotating when you plug the pump in next spring. The gunk setting up inside the pump's housing is usually the cause of magnetic type pumps burning out in the spring.
Even if you have an oil filled pump, in pond or out of pond,just cleaning out the impeller housing is a worthwhile job.

To clean a mag pump, first remove the impeller cover/housing [usually four screws hold it on] and ease the cover away from the pump body.
Carefully pull the impeller out and away from the body of the pump, straight out, as the shafts are made of a ceramic material and can snap if bent or twisted.
You will feel a slight resistance, this is just residual magnetism in the rotor, keep pulling the impeller/rotor assembly out.
Once you have the impeller/rotor out from the pump cavity, wash all the gunk off/out using an old[or new if you like] toothbrush or small bottle brush.
Dry all the parts with paper towel, put a little dab of vaseline on the ends of the rotor shaft and re-assemble.
Your pump is ready for next season.

There is more information on winterising a pond in the FAQ link below.

http://faq.gardenweb.com/faq/lists/ponds/2003010923017442.html
DRH [David] who contributed the winterising article, along with Ronaye and Steve, uses an aquarium air pump and air-stone bubbler in his pond in Vermont [Zone 4] all winter long to keep a vent hole open in the ice.
I use a small pond pump to keep the water surface moving over a large area, so it does no freeze.
There are various methods/devices used for venting ponds.
Water or air pump driven aerators, electrically powered de-icers, stock-tank heaters, home made light bulb de-icers, all ranging it wattage's from 60 to 1500.
Some do the job some don't.
Installing the type of device you are planning to use, should be done NOW.
Don't wait till the pond is covered with ice and snow, it is a hateful job trying to vent an iced over pond.

Having a back-up, like Sandy has, is a good idea also.
These de-icers can fail, just like anything else, so having something else to take over is prudent thinking.

Whatever method you choose, having it in place and functioning, prior to a freeze up, gives the device a better chance of doing it's job.
"Horton"

Thank you, Horton, for giving the link to that FAC. I'm embarrased to admit I have completely forgotten to mention it this year even though almost everything I have learned about ponding except for the occasional personal experience ie., disaster, I have learned from David and you and a few other gurus on this forum. I am usually better about giving credit where credit is due.
Lara, where the subsurface floaters are concerned, a number of them are perennial and will put up new growth in the spring. Which ones they are would have to be looked up.
You could try to use a net on the bottom debris but it will have a tendency to scatter. It seems everyone has a favorite way to get it all and I have tried several methods including a fairly expensive shopvac that proved to be too much a temptation to someone. I recently bought a Phython Vac which seems to work well if your hands are large enough to unscrew the catch chamber but I seem to grab a vac for a child's pond that hooks up to a hose and diverts debris to a cloth bag if I am lazy. The drawback to that one is that any really fine material gets blown back into the pond water. Since I have a good catcher and pump for the Skippy filter that isn't a problem for me but it might be for someone else. It can get clogged by really large leaves still connected to a stem or bunches of leaves. Since it depends on putting water into the pond, you also need to remove water from the pond as you would do for a partial water change. I just purge the Skippy. The Python has a diverter to keep the gunk from mixing it up but I haven't used it long enough to recommend it yet. Maybe someone else has an opinion. It might not be long enough to reach to four feet, my pond is three feet deep. Of course after I put in my pond, everyone started touting the bottom drain systems. Sigh... that will have to wait a while until I get around to making my pond larger. Sandy

I live in Utah, so have winters very similar to yours. My pond is 1,000 gal as well, with a depth ranging from 18-28 inches, and I keep the pump running through the streams and waterfalls 24/7 all year long. Last year we had 3 straight weeks where the temps were between 6-19 degrees. Never any higher.

I keep an electric de-icer in front of the skimmer and that keeps the water moving. Additionally, the pump moves water at a pretty good rate - 4,500 gal/minute - so that helps.

I've noticed during the past 2 winters that when it's really cold the water freezes for about 2 inches deep, and it's liquid below that. The ice freezes on top of the streams, like in the mountains, but the water moves freely under the ice. It's really very pretty.

When we have the warmer breaks in the weather, as we invariably do in the mountain states, the ice melts and I disconnect the heater until the next cold spell.

The fish have all survived beautifully each winter. I don't feed them; I do check on them to be sure everything is OK. When the temps are cold, they spend their winters lounging in their tunnels and I rarely see anything more than a peek of their tails and their noses. I have 3 tunnels for 15 fish that range in size from 14 inches down to 4 inches. The vast majority of them are 8 inches or less.

Also, water does evaporate, even when it's cold and it has snowed. So I always monitor the water level of the pond and add more, when necessary. This amounts to usually once a month, I need to add water to bring it up to the max fill level.

Also, once a month, I'll put on my waders and climb into the pond to pull out algae or leaves that have blown in. I like to keep debris and other vegetation (except the sunk aquatic plants that are over-wintering) out of the pond so the water stays clear and clean -- and it always is clear and clean.

Hope this helps. We are lucky in that our mountain weather rarely stays cold for long periods of time. I think that makes it much easier on our ponds and their inhabitants.

Thank you everyone for the advice! I tried to get to the bottom of the pond with a net, but 'tis not long enough. So, perhaps the shop vac will get to try.

One other thing - has anyone heard of a "pond breather"? It doesn't de-ice, so much as freezes into the ice and continually pumps water up into a chamber for gas exchange. Seems like it keeps an airvent open and also has a bit of a bubble stone effect. Can't find a review online of the thing, so any thoughts are appreciated.
Thanks again, from me and my fishes!

Lara

I know of some people who use a solar cover with an A-Frame to hold it in place. They say it keeps the water from freezing and enables them to keep their pumps and filters running, but I've never had experience with them, so I can't say if that's true or not.

Lara, try the link below.
"Horton"

Here is a link that might be useful: Pond Breather

I'm of the opinion that a bubble creating device is the best approach to maintain a hole in pond ice. I've used turbo ventures connected to small pumps for years. In my experience, the bubblers work well until the temperature falls into the lower teens (Fahrenheit). Its a good idea to have a stock tank heater available in the event of prolonged cold or deep snow. I purchased one last year after a storm dropped over two feet of wet snow that changed to ice in a few hours.

I've decided to apply a Green approach to my pond this winter (energy not algae). I purchased an aquarium air pump from Walmart last week and I have two air stones currently supplying bubbles to my pond. I also have my pump and ventura ready to be turned on and the stock tank heater on standby. I'll run the 4 watt air pump until the 40 watt ventura and pump is needed. I hope the 1500 watt heater stays in it's box.

I also add some zeolite to my pond in a filter sack. It's commonly called ammo rock and it absorbs ammonia while my biofilter is shut down.

Hey, John. I don't depend on a bubbler after the first time I tried it. The temperatures dropped below freezing one night. The next morning, there was over an inch of ice except where the bubbles came up. Each bubble carried a drop of water which froze when it hit the air and created a dome. By morning the bubbler had half emptied the pond drop by drop and I had a skating rink behind the pond. I'm glad I didn't sleep in that morning. Sandy

You should do some research about winterizing your pond. You won't feel so panicked next year, but you learn as you go. We leave the hornswort where it is and cut back the hardy marginals around the edges. Some plants in containers, like the water lilies and other hardy plants in pots get cut back and moved down to the bottom of the pond for the winter. All the tender plants should be taken out before it gets too cold as they will die and rot in the pond.

We always turn off the pump. It gets way too cold up here. And you should have stopped feeding your fish when the water temperature drops to 50 degrees. The fish can't process the food anymore and it could potentially kill them.

We have always used a bubbler. And, yes, if it gets cold enough or we don't have a thaw, it will freeze over with an ice dome in which case we bring out a deicer to open a hole. It doesn't cause any problems if an ice dome forms over the bubbler. It's still creating movement and oxygen and will eventually open up. Whatever you do DO NOT try to open a hole yourself by cracking the ice! You can damage your liner and kill your fish with the sound waves that would create. Buy a low watt deicer now so you're ready. Some use more watts than others, so pay attention to that.

We put our bubbler in the middle of our pond - water has never spilled out. Not sure what happened with the above poster to cause an ice rink behind his pond. Maybe he has a smaller pond or the bubbler was too powerful and threw the water too high. A bubbler just moves the water - it won't keep a hole open if it gets cold enough. For that you'll need a deicer.

I can't say much for the de-icers as we seldom even get snow/ice here in Texas, but I'd like share my personal info about the wet/dry vac in response to your question about cleaning out the muck. I just bought a Ridgid wet/dry vac last wknd and did a thorough pre-winter cleaning on my pond, which has boulders and gravel. I couldn't believe how well it performed. Granted, it does suck out the water pretty quick, so you have to start it up when your nozzle is at the area you want to clean. It doesn't give you a lot of extra time to relocate your nozzle. I used the Python hose-powered vacuum for 5 months and really did not like it at all. First of all, it wastes tons of water bc you have to run your faucet on high the whole time for the suction. Secondly, it doesn't have the suction power you need for a pond. Lastly, the debris catcher is so hard to open and close because it doesn't have any grips for your hands. I'm throwing away my Python vacuum as I will never mess with it again. It truly was a waste of money, in my opinion.

After my experience, I believe every ponder needs a wet/dry vac or something similar. It has made such a difference in my pond. I was even able to vacuum out the shallow stream, which my Python could never do (it requires a certain depth of water).

Just my two cents! :)

Sandy, I can't imagine a bubbler draining a pond. My bubbler freeze over every winter and I do get a dome of ice, but I've never had any water loss. The water level in my pond is usually a few inches below ground level. In the winter, I reduce the level to about six inches below ground level. My bubbler is also several feet from the edge of my pond. It would take a very large ice dome to have any effect. Is your pond above ground level?

Along with maintaining a hole in pond ice, a bubbler helps bring harmful gasses to the surface. It also keeps a healthy level of oxygen in the pond water. I never made it through a winter without the ocasionally use of a heater, but I won't shut the bubblers off until the spring.

Hey, Johnkr. Indeed that was one of my first ponds when I was feeling my way through all the permutations of pond designs. Yes it was partly above ground and the bubbler was in fairly shallow water (18 inches), only a foot from the edge and the air flow too high for that depth. The turbulence practicaly threw the water out of the pond and the high winds that night didn't help much. The partial dome prevented the water draining back into the pond and since it had started with the water level right up to the rim the water had no place to go except over the edge. The ground was already frozen so the puddle formed and froze. Who knew? I was a novice and way too many things didn't occur to me before I found a problem. It has always annoyed me that instructions will tell you how to do something and not why or what problems will show up. Sandy