I'm in central Il. I leave my lillys on the bottom and my Iris on the shelf. I don't move them.

I detach my biofilter in late November (primarly just to filter out particulate matter). I leave my pump running 24x7 all winter, with the water just recirculating.

I also leave my bubbler on 24x7.

I reattach my biofilter in march/april.

Last winter was brutal and my pond froze about 12-18". Fish did fine.

Thanks groundbeef!

What about my water fall and small stream. Should I just unhook the hose to the pump and let the pump just circulate the water where it sits, shutting down the falls all together?

I am very curious to see what this first winter will do to my 350+square foot, 5000+gallon, 3 foot deep pond.

I am colder than you are but here's what I do.

As the water temp starts cooling in the fall I switch to a cold water food, then when the water temp reaches about 50 degrees I stop feeding them. According to what I have read, their digestive systems start shutting down around 50 degrees. If they are hungry there is always algae or insects of some kind available.

I have tried different techniques through the winter. I always shut down the stream and waterfalls as the ice would make them overflow and empty the pond.

Sometimes I have just dropped the hose into the pond and left the pump running. Sometimes I have used a bubbler, but last winter I think it quit or froze up. All my fish died, so I'm not doing that again.

I may go back to using the pump and add a de-icer to keep a hole open.

I usually cover the pond because it is only 2 1/2 feet deep and a severe winter might freeze it too much.

In the spring, after the ice has melted, I put the thermometer in. After the water has warmed up to 50 degrees I start feeding the cold water food and then switch over to regular food as it gets over 65 degrees.

I dont know if any of this is "right" but it is what I do.
Anne

@pcan

I run the outlet hose on the pump to the edge of the pond, and point it downward to the pond surface, about 1" off the top. It seems to keep a hole open for a bit, and aerates the water somewhat.

I do not keep my waterfall running, as I'm afraid of some sort of icedam that would develop and potentially divert the water OUT of the pond. That would be catestrophic.

pcan, near Reno, a lot like the Wasatch Front with less precipitation, my spouse tapers off feeding in September and then turns off the filters when the water temperature gets about 50F. She leaves the aerator on all winter. This has worked well.

She leaves the plants removing, and not replacing, any that do not survive the winter.