Our main water tank carries 170 L (45 US gal), our secondary has 50 L (13 US gal), while an additional 100 L (26 US gal) is stored in jerry cans.
When it is not possible to dock at a marina, we use smaller(4x10L|4x2.6 US gallons) jerry cans to ferry water from shore. While it requires more trips, the lighter containers are less prone to breakage. When filling up, we filter the water.
Pino has no watermaker, and doesn't want one.