CavemanCharlie wrote:
...
I thought AGM batteries took a different type of charger ???
Nope. Usually it is the flooded battery that needs a special charger.
The serious problem arises because Optima AGMs have a higher 13.1 resting Volts where flooded(FLA) has 12.65. These two cannot be left connected because the Optima will try to charge the FLA! When the Optima eventually drops to 12.65V, it is only about 75% charged.
If you know what you are doing, you can use them connected and charge them connected. If left standing, you need to disconnect. There are electronic battery separators that can help.
HTH;
John