Living at sea

[emzie]

Vitamin C could be extracted / harvested from kelp. Or you could eat like 2kg of kelp a day.

 

[Patroklos]

You can live with vitamin deficiencies, so just because people have made a living from the sea doesn't mean they were as healthy as they could have been. Certain edible seaweeds are an excellent source of calcium, iodine, magnesium... but they're found near shore and even then, not everywhere near shore. They don't grow in the middle of open water. I'm not sure there's much point in having a don't-go-to-shore rule if you need to be within a country's territorial waters to harvest kelp.

Are Eskimos known for being unhealthy? In any case I figured the point was to not touch land, I figured the littorals were free game.

If you can't go close to shore algea screens could be an option.

As a mariner, you'd know this... would it be feasible to create a hull that wouldn't need dry-dock maintenance over the length of a human lifetime?

I doubt you could make it last a whole lifetime but if you diligently maintained a modern steel hull you might get thirty years out of it, though its utility would be suspect beyond simply floating at some point.

 

[Souron]

You'd have to have to have some good hydroponics if you want to be totally isolated.