Various embodiments of an aquarium and its method of use are disclosed. In some embodiments, the aquarium includes a first container for holding water and fish, plants, and/or other aquatic organism, a second container for collecting dirty water, and a passageway arranged to flush water from the first container to the second container. The passageway is in fluid communication with an outlet of the first container. The second container is arranged to receive the outlet such that fluid flows from the passageway, through the outlet, and into the second container. The outlet may be selectively opened by a user via a valve. Opening the valve causes gravity to flush water and debris from the first container, through the passageway, through the valve and into the second container, where the dirty water can be stored or discarded by disconnecting the second container from the aquarium ad dumping the dirty water.
