This Philips non-spherical-biosphere is a self-contained farm for that produces hundreds of calories of various food sources a day. Its five-level design breaks down like this:

Levels 1 and 2: Plants
Level 3: Algae
Level 4: Fish and Shrimp
Level 5: Organic Waste

From what we can tell, the system is designed to cascade nutrients from the top to the bottom (back to the top). Optical fibers capture and redirect light to the plants during the day, while methane capture from organic waste can power lights at night. The algae create oxygen for the fish.