I have two batterys with a switch should they be two starting batterys or deep cycle i dont use my electronics alot when the motors are turned off its a 150 mercury o.b.
that depends on how you use em... if you will occasionally run a batt to half charge or lower then it needs to be a deep cycle.. If you will be starting a motor w a batt then it should be a starting batt... If both (not the best plan) then it should be a dual purpose....
MY choice is one starting batt and 1 or more deep cycle batt with an ACR between em... Then wire EVERYTHING except the engine to the D/C batt.... This keeps the start batt fresh for starting.