An aquarium fountain for the improved circulation in a cascading manner of a fixed quantity of particulate matter such as sand. The fountain includes a housing having a receptacle for containing and receiving the fixed quantity of sand. The housing includes an air lift tube having an inlet end in communication with the particulate matter to be circulated and an outlet end out of which the particulate matter is expelled. The outlet end of the air lift tube extends into an upper chamber of the housing. The upper chamber is configured to have an air pocket located between the outlet end and an air escape opening located in a wall of the housing.