Shore power and Battery Power

Question
I recently purchased a 2006 300 Searay Sundancer.  I am a first time boater.  Dealer made available a Captain along with several lessons. We tied up to my home dock set up the shore power connection. One of the dock hands mentioned to me that I should leave the batteries on even while the shore power is connected.  Not what my Capt recommended.  I thought according to the manuals and the Capt., Batteries on when boat is not in use adds to Battery hours.  the batteries will charge normally when underway.  Is this so? Which is correct action.  Thanks Much.

Answer
Hello Ray...Thank you for selecting the undersigned to reply to your question.

Your Capt. is correct. While on shorepower, your batteries are not being regenerated. They regenerate when the engine is activated or a battery charger is being utilized. Shorepower is beneficial when at dockside and you are desiring to operate an AC/DC stove, refrigerator, cabin lights, TV, or other accessories, etc., without draining your batteries. Batteries are essential to start the engine(s).

Safe Boating
Ron