Looking at the year of your RV I suspect you are not using an on-board SMART MODE Converter/charger unit.
The smart mode converter/chargers will really take care of your batteries for you.
Also on the previous post about taking care of things. The best you can do is NEVER EVER run your batteries down below 50% charge state which is around 12.0VDC. Then promptly re-charge them back up to 90% charge state and you can do around 12-14 charge cycles from the 50% - 90% charge states before you have to do a full 100% charge state. Using smart mode charging technology you can get re-charged in as little as three hours of charge. Doing the full 100% charge will take around 12 hours of charging...
This is what we do with our multiple deep cycle battery bank. I am on six years now for my three GP24 85AH Interstate batteries (255Ahs) in my 2008 OFF-ROAD POPUP camper which is mostly used for camping off the power grid. Lots of charging cycles...
Roy Ken