And Another Battery Question

Having used GC2 batteries for many years, both myself and my son have seen voltages similar to yours. They seem to charge up fully, and when in use drop down in voltage to around 12.6 or so. Not much below fully charged. The biggest plus for them is that they hold the charge and last longer than most 12V batts for some reason. The real number is what your voltage is in the morning, esp if using furnace in cooler weather. Our 4-1/2 yr old 6Vs will be at 12.2 or so in the morning and recover very quickly when the sun starts shining. Sons act similar. Personally (with no actual proof!!) feel that this is a normal pattern for a true deep cycle 6V pair!!

Also, hydrometer almost always shows above 1275 when recharged!!! Never have checked in the morning, no problem, no fault!!!