A pump monitoring system configured for installation in a reservoir for holding liquid, the system comprising: a level sensor configured to be installed in the reservoir and configured to, in use, monitor a liquid level in the reservoir and generate a level data based on the monitored liquid level; a current monitor configured to be installed with a pump associated with the reservoir, and configured to, in use, monitor a current consumption drawn by the pump and generate a current data based on the monitored current consumption; and a controller, characterised in that the controller is configured to, in use: receive the level data and determine a static head from the level data and generate a head data from the static head; receive a first current consumption and head data corresponding to a first current consumption drawn by the pump as a function of the static head for a first period of operation of the pump; receive a second current consumption and head data corresponding to a second current consumption drawn by the pump as a function of the static head for a second period of operation of the pump, wherein the second current consumption and head data is recorded when the liquid in the reservoir is between a first liquid level and a second liquid level, and wherein the first current consumption and head data is recorded when the liquid in the reservoir is between at least the first liquid level and the second liquid level; and process the first current consumption and head data and the second current consumption and head data to determine first difference data representing the difference between the current consumption drawn between the first liquid level and the second liquid level in the first period of operation and the second period of operation, the first difference data providing a pump performance indicator giving an indication of the condition of the pump. a level sensor configured to be installed in the reservoir and configured to, in use, monitor a liquid level in the reservoir and generate a level data based on the monitored liquid level; a current monitor configured to be installed with a pump associated with the reservoir, and configured to, in use, monitor a current consumption drawn by the pump and generate a current data based on the monitored current consumption; and a controller, characterised in that the controller is configured to, in use: receive the level data and determine a static head from the level data and generate a head data from the static head; receive a first current consumption and head data corresponding to a first current consumption drawn by the pump as a function of the static head for a first period of operation of the pump; receive a second current consumption and head data corresponding to a second current consumption drawn by the pump as a function of the static head for a second period of operation of the pump, wherein the second current consumption and head data is recorded when the liquid in the reservoir is between a first liquid level and a second liquid level, and wherein the first current consumption and head data is recorded when the liquid in the reservoir is between at least the first liquid level and the second liquid level; and process the first current consumption and head data and the second current consumption and head data to determine first difference data representing the difference between the current consumption drawn between the first liquid level and the second liquid level in the first period of operation and the second period of operation, the first difference data providing a pump performance indicator giving an indication of the condition of the pump. receive the level data and determine a static head from the level data and generate a head data from the static head; receive a first current consumption and head data corresponding to a first current consumption drawn by the pump as a function of the static head for a first period of operation of the pump; receive a second current consumption and head data corresponding to a second current consumption drawn by the pump as a function of the static head for a second period of operation of the pump, wherein the second current consumption and head data is recorded when the liquid in the reservoir is between a first liquid level and a second liquid level, and wherein the first current consumption and head data is recorded when the liquid in the reservoir is between at least the first liquid level and the second liquid level; and process the first current consumption and head data and the second current consumption and head data to determine first difference data representing the difference between the current consumption drawn between the first liquid level and the second liquid level in the first period of operation and the second period of operation, the first difference data providing a pump performance indicator giving an indication of the condition of the pump.