Yes, it should function as a normal pot until you introduce the lower pool of water. At that point they'll have to convert the lower roots over to water roots which could take 10-15 days if you don't put any water in the reservoir from the get go. Some of the water will evaporate into the connector pot and the soil roots will sense it and begin their transition.I’ve been thinking about the water pot for the Watermelon WeddingCake. I’m wondering - as long as I don’t put any water in that res, this thing should simply function as a pot, right? When the roots hit the plate that separates the water from the not water, if there IS no water, then the roots will simply curl around like in a normal pot, yes? It’s not as if they’ll reach for plain air, but if they land on water they’ll grow into it, right?
And they will grow into the water and if you go with your air stone idea, they will likely fill that lower chamber with hydro roots.