I try to mix things up a little. Same size family, + 2 dogs. (4) 7 gallon Aquatainers, (2) 5 gallon jugs, roughly (5) 1 gallon jugs, always at least 2 cases of half liter bottles, plus (2) 40 gallon water heaters. The 7 gallon jugs are at the upper end for portability, and then for only short distances by hand. I keep a limited supply of chemical purifier pills and there's always a couple jugs of bleach in the laundry room. Bugging in, we're ok for at least a couple weeks; bug out by car, several days; on foot - limited to what we can carry, collect and purify.