The filter no long sucks in water.
Please clean all the hoses, pipes and the filter to remove any biofilms, algae and mud in them. It is not enough to simply rinse with tap water. Make sure to use the JBL Cleany hose brush for cleaning. Remove the water from the body of the filter and the hoses. Make sure that the two small stopcock levers on the pump head are in the “OPEN” position. During the following start up procedure, the water outlet pipe with the spray bar, etc. must be positioned ABOVE the surface of the water for optimum ventilation of the appliance. Press the “START” button on the pump head repeatedly with the palm of your hand until water begins to flow into the suction hose (hose on “IN” ). Wait until the filter has filled completely with water and the water in the hose leading to the water outlet pipe (hose on “OUT”) is at the same level as the surface of the water in the aquarium. Connect the filter to the mains power supply. The water will now flow out of the water outlet pipe and into the aquarium. At first, it may be mixed with air that is still trapped between the layers of the filter media. Gently shake the filter to dislodge the air which will escape with the stream of water.