My L16's are Trojans not US Battery BTW. People think I spend a lot of time on my batteries. I really don't. There is the odd geeky experiment here and there but they just sit on float most of the time. My crappy Iota converter has made me visit them more often lately but since I got the power supply, that will change back to what it was before. I filled them with water a couple weeks or so ago. Last time I messed with them was back in February after an off grid trip. Honestly, once I have a good SG in the bag, I don't need to mess with them at all. I only need to make sure the converter (now power supply) is still working. When I first got them I was out at the RV a lot but once I figured out how they work (charging, hydrometer checking etc), time spent is drastically reduced. About all I do know is make sure the charging source is still working.