Jeff, I wish it were as simple as more aeration. From my experience and what I've learned on this forum it can also be very dangerous to over aerate in the winter. I only aerate one end of my pond 8 hours day in the winter and while it does keep an area open and keep the ice thinner it also cools the water. My fish always stay as far away from the aerator as they can. Water temp readings show that there is no stratification near the aerator so the water is cold at all depths. The real key to fish survival seems to be keeping snow off the ice so the algae can do it's photosynthesis thing. I plow my pond all winter. I think my aerator mainly just keeps the ice thin enough to keep things from freezing to the bottom. I also really enjoy hearing what challenges all the folks in different parts of the world are going through. Dr. Willis, are you surprised that my fish survive in such a shallow pond? I am. Last winter the majority of my pond only had 2 feet of water under the ice. I can't believe this works.
