Fly the Team Iceshanty Flag! Iceshanty Proshop
OK..The consensus is "don't put anything in the water that shouldn't be there". All kinds of gadgets and gizmo's to keep the hole from freezing..
Egg beaters are the most eco friendly way to go. Just go to one side of the tip up and beat the water like it was an egg. Your hole will never freeze over.
"Call now and we'll double your order" I can see the info-mercial now!!!
In all seriousness try ping pong balls spray painted black... sheesh...