small charger for AGM?
I have a friend who just purchased a couple of 18ah AGM batteries and needs a good charger to keep them healthy. They are 12v each and will be used to power a 12v CPAP machine overnight in the event of local utility power failure, so sort of a poor man's UPS. Can anyone here recommend a reasonably good, intelligent 3 stage charger for a battery of this size? I think both batteries will be wired in parallel and the charger will be plugged into a standard 120v wall outlet, this is not solar related (sorry!). I tried the 'bay but get deluged with hits and didn't know how to filter them, there's so many differents ones and I have no idea which ones are good and which are flakey. Probably all are built in china, but I don't know their track records...
my thanks and aloha,