Re: Battery Drainage?
Having a second battery on board is always a good idea but not always practical. If you have the room to stow a backup then by all means carry one.
Cd players/ stereos and the like can use power when they are turned off. Some draw power to keep the clock in time or power a remote circuit. Still other radios need power to keep memory settings like radio stations and the like. I wired mine in my little boat with a main power switch so that I can kill all power to it when it is not in use. I can scan for radio stations, and I don't really want to know what time it is on the lake anyway.
Since you are going to be using your boat for day trips it is unlikely that you run the battery down to a point that the engine won't start, but it is possible. If you want tunes all day and you are in to big amps and lots of speakers, then you should get a second battery. If you just want some light Beethoven or Vivaldi with your fishing, you should be fine. By the way, keep it down your scaring the fish.
