If possible adjust the voltage setting on the controller.
For lead acid
storage in the tropics, set the voltage at a point where no gas is given off or ~13.2V. That way you will return to wet batteries.
For
AGM batteries, use the float voltage for the batteries. This varies with manufacturer and temperature. We use ~13.6V.
There is always a possibility that the drain hole in the
bilge will become plugged. Keeping your batteries up and your
bilge pumps active is advised.