Coolant- What To Use?

The last time I raced regularly, we used water, and drained it in the winter.
I know the tracks don't like antifreeze, though a zillion street cars go down the track.
The car has brass freeze plugs. I kinda remember reading about using some kind of additive? Maybe to prevent corrosion?
In addition, I've read about the coolant having an electrical charge? Something about using an anode?
I are con-fused.