Abstract: A self-contained closed aquaponics system comprises an aquarium tank attached side-by-side to a water container for growing plants, having a shared side. An electrically powered water pump streams the water from the aquarium tank via a pipe to the bottom of a compartment in the water container. When the water in the water tank exceeds a pre-set water level, the water are poured back to the aquarium tank via a recess or slit in the shared side. The compartment may comprise a bio-filter that is a sponge filter, a foam cartridge filter and the undergravel filter. The aquarium tank or the water container may be rectangular or cuboid shaped. A cover adapted to cover the water container may include multiple openings for mounting plants in pot nets therein, where roots of the plants are fed from the fish excretions in the aquarium tank after being filtered by the bio-filter.