On 22 Mar 2007 09:50:20 -0700, "
wrote:

With this understanding, I am certain that I
will buy AGM batteries (instead of flood batteries) to take advantage
of the fact that I will not need to pull them out from the boat every
winter to refill water (like what we need to do for flood batteries).

Batteries that are kept fully charged will not freeze so there is no
need to pull them from the boat. AGMs and gel cells require special
charging precautions that I prefer not to deal with, not to mention
the additional expense. The best $$$ value for trolling batteries (or
any other deep discharge application) is 6 volt golf cart batteries
wired in series to yield the proper voltage. Approximately $50 each
at Sam's club, years of reliable service.