Prefetch - One thing that really has been a vital tool in my quest to get fish to survive the winter has been a dissolved oxygen meter. Some folks will say it is unnecessary, but I don't see how I could manage my lake without one. It sucks because the meters are not cheap. To me, trying to understand what's going on without knowing where the oxygen is at is like feeling around in a dark room. I still don't always understand exactly what is happening up there, but I at least have a much clearer picture. That's just my experience though.
