I think I told you to check out DC Battery in Miami because they had an efficient method of delivering all over the Caribbean and you could not find GRP 31 batteries in PR.
However, you are now in Tortola. I would research what is available in Tortola ans St Thomas.
There is probably no doubt that you are beyond the replacement date of your batteries and your charger is cooking the batteries. Your charger is reading the internal shorts and resistance in those batteries and interpreting it as the batteries need more amps and the charger is delivering them.
Since you are connected to shore power, all you need is two good 12VDC batteries connected in series = 24VVDC. And you do not need a starting battery. Use a digital tester to find 2 good batteries out of the 9 you have then connect them in series to the house bank. Use your smallest charger and ASAP find NEW batteries.
BeBe Amel 53 #387
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