How old are your batteries? It may be just the corroded connections making your batteries look bad. Before buying new batteries I would clean all of the connections and try charging them again and see how they look.
Also, I would strongly consider using a pair of 6 volt golf cart batteries hooked up in a series instead of 12 volt batteries. I have been using golf cart batteries for many years and they last longer than the 12 volt ones that I used to use and have more capacity. I just added 4 Trojan T105 golf cart batteries and unhooked the single 12 volt battery by the slide pump. It gives me a fair amount of capacity for while we are dry camping like we have been for the last 6 weeks and will be doing for the next 8 weeks. I hope this helps.
I think that 6 volt batteries are really good advice for someone that dry camps. However if you are just your everyday camper going to parks with full hookups I think the "12V maintenance free deep cycle group 27 RV batteries" are a better way to go. You will not have to keep checking the water levels and keep filling them up.
You can just use them hassle free for many years.
Now if your someone that keeps using your batteries up then recharging them often the 6V are a much better option.
This is just my opinion and what I use.
Jerrod
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