Richman, Get your self AC Delco Voyagers. either 27 or 30 models. They are maintenace free, no filling of water, or battery acid to deal with. I had a set in my boat for over 5 years and are still going strong. I just got a new boat and put
3 30's in the boat. @ 108.00 each...They are the best I have found for the price, and not have to do anything but go fishing.
Also get your self an onboard charger, they will help to make the batteries last longer....