Originally Posted by jasum
You should be more than enough for a weekend, probably longer.
Obviously it depends on how much the toilet is used......
Agree, two nights is pretty easy, even with daily showers. We just came back from three nights of dry camping in our X213 (48 gallons freshwater, 30.5 black, 22.5 grey) and it went great. Came back 2/3 on both waste tanks and 1/3 on freshwater.
1. Showers are the biggest consumer of water by far, so learn how to do a military style shower and you don't use much water at all. Or consider wet wipes (they make adult ones, too ;-)).
2. Wash dishes with bins of water just like you would tent camping.
We also bring bottled water for drinking, which probably doesn't make much of a difference but every little bit helps.
Battery power has been more of a concern for us than water & waste. We have two 12V 85Ah batteries and it's reliable for 2 nights, but 3 is pushing it especially if you have to run the furnace at all. I bring a 2000W generator just in case, and we did use it this weekend for a few hours on the third day to bring the batteries up a little.