I noticed that my pond has frozen over. It typically never does as I have my aerator still running at night. I found out that I need to replace the vanes in my pump. The issue is it will take over a week to get the replacements. My question is, once I have the pump fixed should I go head and start the pump and hopefully create a hole? One issue is that I neglected to move the diffuser to shallow water last fall. I have left it in deep water over winter before with no issues. It would typically keep an open spot in the ice.
Thanks

I wonder if the ice is thick enough to walk on and if it is maybe drill a couple holes above it with an ice auger. The hole just might open back up. Of course drill the hole BEFORE you turn the pump on.

Generally, the point of a hole in the ice is to have enough open water (stirred by the aeration) to transfer sufficient oxygen into the pond to keep your fish alive.

gklop, if your ice is as snow covered as mine is, I'd turn the aeration back on once the pump was fixed. If you haven't hurt your fish with the diffuser in deep water during past years, it should be okay now as well.

On a side note, you might not have to run the diffuser 100% of the time to ensure sufficient dissolved oxygen (if that is your main goal for winter aeration), but if it works for you, it works for you.

Ice won't last a more than a day over a running diffuser.

I am leery of aggressive aeration during the winter when temperatures are cold enough for ice cover. The stratification that naturally occurs under the ice provides a warmer refuge near bottom where the fish are a couple degrees or more above freezing with cooler water being up top in contact with ice. The couple of degrees difference may help the fish contend better with health issues that become more problematic as temperatures approach the minimum the fish can tolerate. When you aerate aggressively you can have a temperature profile where essentially freezing temperatures are realized all the way to the bottom of the pond making so fish are exposed to temperatures colder than they can normally avoid. The super cooling can be particularly problematic with an open (ice-free) pond exposed to sustained very cold wind. You can often expect to see a major increase in fungus growth on fish as secondary infections a couple of weeks later when they are exposed to temperatures that are too cold for too long.

As noted above it is a trade-off between temps (super cooling) and enough O2. If you are going to repair and place back in service move the diffuser shallow.

Thanks for all the input. Since we are going to have frigid temps for the next couple of weeks I think I have a plan. I have an old diffuser that I think is still useable. It is not a disk type and I don't know if it has a check valve. Hopefully I can break a hole in the ice in a couple feet of water and drop this one in for a temporary fix. Hopefully it will create some open water.

Thanks again

In one of my ponds I have a simple airstone in shallow water for Winter aeration use. It blows great big bubbles, rather than tiny Don Ho sized ones, but melts a hole in the ice no problem.

Big bubbles are better in the winter for keeping a hole open than small bubbles.