>>22884809
Good stuff anon. Yes pocket filters are only for short term scenerio.
>>22884812
Don't rely completely on distillation. You'll need to save fuel, avoid heat signature and faster methods. It also needs to be passive.

Learn to make a charcoal slow sand filter.
schmutzdecke is what actually filters the water. See https://www.slowsandfilter.org/f_valve.html