The first recommendation is to change out your converter to one that includes a 3-stage battery charger. It's not recommended to use a single-stage charger/converter for long periods with lead-acid deep cycle batteries and doing so will reduce the service life of the batteries.
The second recommendation is that once the batteries are fully charged, I'd measure the state of the batteries with a hydrometer (cost you $10-$20) and replace either of both batteries if the specific gravity measures low after a complete charge (don't forget to correct for temperature).
2015 30' Classic, "Chez Nu"
2014 RAM 2500 w/Cummins Diesel
ProPride Hitch, 400 W Solar