Look into the trimetric 2020. It's good from 12-48 volts, and will tell you just about everything you want to know. I have one and love it. http://www.bogartengineering.com/trimetric.htm
To be honest though I think your battery amp hours is closer to 400, not 800. If they were hooked up as a 12v system you might get 800 amp hrs, but when you wired them for 24 volts you only get half the amperage. You'll need to know the correct figure to program the battery monitor.
She's a tired old barge but she's paid for! http://s71.photobucket.com/alb...p;current=ef324993.pbw
01:44:54 PM by