40 gal fresh tank, 35 gal GW and BW each. I also carry three water cooler bottles that total 16 gal I fill at the campground spigot. I dry camp between 5 and 7 days, three times a year and only once or twice had to refill the water bottles. My only limitation is my black tank as the campground I go to allows grey water to be seeped out into the woods with a hose. I did fill my black tank to capacity once while having 6 people camping. Fortunately, the campground has a mobile dump service for a small fee. Since then, the boys, myself and my two sons have taken to the woods for bladder unloadings. Saves a many gallon in the grey tank for the other business.