Abstract: A pump having a pump chamber arranged to receive liquid to be pumped and air, a delivery pipe for delivery of the liquid by the air to a location remote from said pump chamber, an air pipe for flow of air therein. The delivery pipe and pump chamber are in fluid communication, as are the air pipe and said pump chamber. A first air flow control to control air flow via said air pipe during first and second stages of a pumping cycle of the pump. A timer controls the operation of said first air flow control to thereby set the durations of said first and second stages of said pumping cycle. A first valve allows liquid to enter said pump chamber. Wherein in said first stage of the pumping cycle of the pump, the first air flow control allows air to be directed via said air pipe to said pump chamber for a time period set by said timer to cause liquid to be pushed from said pump chamber into said delivery pipe with the air for delivery via said delivery pipe to said location.