I always wondered where excess salts and nutrients go in an EarthBox / eBucket.
To a novice, it seems like everything that goes into the reservoir has to enter the soil, then evaporation leaves it at the soil surface. But I've never done an eBucket.
It does seem to me that the air reservoir created in most designs must be A Good Thing for root aeration. I assume there is some opening that lets the "air reservoir" exchange gas with the atmosphere.
I have some kind of fetish for rapid through-drainage and aeration.