Fuel oil compensation

My only real experience with diesel oil systems is in submarines. There, we kept the tanks always full by filling with seawater as fuel oil was used. Done for trim and in nuclear boats for reactor shielding. Of course, a nice purifier system was always available.

If a passagemaking boat were equipped with a nice purifying system anyway, would doing the same make sense to maintain trim and stability and to keep air out of the tanks?

 

The same results , no free surface area can be done simply by having more tanks.

This allows fuel to be kept clean and the boat in trim.

Most boats will cruise inshore with a modest fuel load only getting really heavy for a long offshore run .

Fuel dies when kept in tanks so the multiple empty tanks are a joy , as they can be totally drained before a filling

.Empty tanks gives no bugs , water , sludge buildup or ancient fuel.

Ob a pleasure boat , most do not require the fuel as ballast , and cruise/operate better in light ship.

FF