I have two 12v wet cells set up in parallel. Now that I read all this, I am wondering about my charger. I can't remember the brand name, but it is a three stage, portable, smart charger purchased at West Marine. It has separate settings for various battery types and charging levels. I believe it is adequate to the task, but someone more knowledgeable might think otherwise. It makes sense to me that the charger ought to be able to charge both batteries if hooked up to one of them and with the battery control switch set to "both". It also appears that there is a difference of opinion on this. Thanks to everyone for the replies, though.