Stackable ebb and flow?

[fintuckyfarms]

So I have been searching the web, checking out the different systems out there and I have a question for those with way more knowledgable then me.

In an ebb and flow system if your reservoir is large enough, can you stack the grow trays so that the top one "waterfalls" into the next lower tray say maybe 3 or 4 trays above the reservoir? Not right on top of each other but off set. My concern would be that the plants will use up the nutrients before they get to the bottom tray. Is this a valid concern? Has anybody seen anything like that?