I wondered about this as i sat on my dock watching my fish eat. It sure looks like a pretty great delivery system to create a little "hot zone" for the winter time. I guess the trick would be able to create the heat cheaply enough. Would a solar panel create enough heat to make a difference? I guess you could basically enclose the aerator compressor in a insulated container that would accept the heat source. I'm sure others have considered this already, but i don't recall seeing a post on it.I guess the heat might be too hard on the compressor.