Jeff, You certainly live in a harsher winter climate but I don't do much with my skimmer to be quite honest.

But in a Green Bay winter you are going to need to probably stop moving water the way you have all summer-long.

Net pond in fall.
Move aquatic plants down or out.
Remove netting.
Late Fall cleaning.
Turn off & remove pump.

Caveat: Remove the pump(s), and if you have fish then establish a large bubbler (alternate pump) to keep at least a small section of pond free of ice.

Unless you get a lot of hard freeze then thaws, repeating, I would think that the skimmer door wouldn't be a problem. I've never considered removing my inlet door (a Savio skimmer).

Some winters I've removed my pumps from the bottom of the skimmer; I think I did that the first winter, then the second winter I turned them off but left them in without issue.

This past winter I ran one of my two pumps all winter. I have two magdrive pumps, about 3700 gpm each, and we've had two really hard winters in a row.

What may be different with your situation versus my situation is that your ice is probably going to be thicker. I had ice the better part of the winter, often thick enough to skate on, but I could see with my setup, which sounds a lot like yours, that I still had water moving into the skimmer & UNDER the ice even as it came over the second falls. That won't be your case.

I think your two areas of problems would be: 1) You're going to have thicker Ice at the skimmer door. Possibly thick enough to dry the pump basin. 2) If you kept the pump running the first part of winter, or started it up early during a lot of freeze-thaws towards the end of winter, when the Ice wasn't so thick, you could get a cold snap, like at night, this could block your bio-falls/weir in a way that ice damns or diversions would form and throw your pond's water outside the limits of your aquatic garden.

If the plastic on your skimmer and skimmer door is thick, like my Savio, I would think you could just leave it. I have heard of people draining their ponds, especially below or to their rock edge, to protect freeze-thaw action eroding their rocks, but I would hate that look of a substantially drained aquatic garden... but you may be under a foot more snow than we typically have here so the appearance my not be of consequence.

I don't know if regular Air Bubblers are enough to keep your Green Bay ice open... maybe others from the far north can chime in here. But the problem I could see with a temporary fountain like pump, say at the center of your pond, is that you could get water pushed up from the pump ON TOP OF the surrounding ice. This just creates more and more ice and could drain a substantial volume of the pond.

Good luck next winter.

Thanks for the info, Pondbucket. I plan to completly shut down down the pond for the winter. I plan to remove the pump and store it inside for the winter. I may bring the fish inside as well - as least the ones I can catch. I may install an air pump and areator to try to keep a hole open for the few fish I miss.

One time at the old house - I tried to keep the waterfall running through winter . . . it looked very pretty at first as the ice formed around the falls ... then like you mentioned; an ice dam formed at night and all of my water got pumped out of the pond.

Jeff

Jeff, there are good air pumps available, durable for hard winters. They just cost a little more than at discount stores. Mine came from a local pet shop. I have two and use one to keep a hole in the pond ice and one to drop into the skimmer. I arranged them so bubbles from the skimmer joined the bubbles in the pond and I maintained a very nice ice-free area in the pond and skimmer. Worked for two winters so far.

I live in zone 5 and what I do is put in a milk gallon filled with 1/4 water, and some pool styrofoam in the skimmer. I run a small pump in the skimmer that has the outlet pipe thru the skimmer door and put an elbow on it so the water just bubbles under the surface. Then I put my pond deicer over this. Has worked very good for years. The pump I use is a mag drive and about 300 gph. Good luck on your pond this year.

Thanks for the replys.
I also sent this question to Atlantic Water Gardens, the manufacturer of my skimmer. I wasn't expecting much of an answer . . . they replied in lass than a hour and said the skimmer is designed to handle freezing water and he said I don't need to drain the pond down or do anything other than remove the pump from the skimmer. He said I would be better off with ice in the skimmer to ruduce the chance of the skimmer lifting during the freeze / thaw cycles

Jeff
I was happy to hear that.