» What it is: A polypropylene fish tank used in aquaculture. It floats and can be connected to other aqua-sphere tanks or a work platform. Because it is closed except for air injection tubes, most solid fish waste and uneaten food accumulates in the bottom of the tank rather than filtering into the water outside the tank.

» Who came up with it: Boca Raton-based Aqua Biologics, a division of Neptune Industries

» The next step: Because some fish waste from the aqua-sphere does seep out of the tank, the company has set up a prototype to produce algae in the water because the nutrients in the water help the algae grow. The algae would be used as a source of biodiesel. “Nothing goes to waste,” says Ernest Papadoyianis, CEO and president of Neptune.

» Funding: For its algae biodiesel project, Neptune recently received a $158,270 grant from the Florida Department of Agriculture and Consumer Services’ “Farm to Fuel” program, enacted in 2007. Papadoyianis says that Neptune will turn to outside companies for the actual biodiesel production.