Martin Schreibman is a man with a vision for the future, and that vision involves a lot of fish tanks - in downtown Brooklyn. Like many progressive thinkers, he is a proponent of creating better food, more jobs, and a better life for people in cities. But his preferred method for accomplishing all this - urban aquaculture - means he is at times viewed as both a revolutionary on the cusp of greatness and as a scientist working on the intellectual fringe.