"I just installed a 2 bank 10amp on board charger that I have hooked up to each battery."

Don't leave both sets of leads hooked up from the charger to the batteries, you may fry the new charger. 2 bank simply means for 2 batteries. Your parallel installation of the batteries is like having 1 battery only twice as powerful. Everything bk said is correct. Check instructions for single bank install. They may want you to use one set opposed to the other, but should not matter. So in other words, only hook up one set of charging leads from charger.