Very cool! Glad to hear your found a farm. I'm sure you will enjoy it. The first two weeks are awesome as the fish become aware of the their surroundings. Most of the swim around the pond in the top two feet of water and hit everything. Good time to wet a line
You will lose a few to predators to this time. I suspect those 200 will keep you very busy fishing wise.
The aeration may actually work in your case. It is important to have sunlight with aeration. Otherwise your just stirring up an oxygen dead bottom. When I would drill a hole in the ice in the pond I had it would smell sulfuric...not good aerating that stuff. It may not stop the winterkill but evey if 10% or 20% survive, look out for the next year!
Cheers!