I'm not a fan of the bluesky controllers. The charging modes leave a bit to be desired.
The charger does need to have a point where it desulphates the batteries. Too low of a voltage will shorten the life just as much as too long at boil point. Those voltages are usually specified by the battery vendor.
One reason Trojan batteries are so popular is they provide all the details needed to tune your charger.
Trojan Users Guide.
Following their charge and equalization guidlines will greatly increase the life of your batteries.