Instructions
Unplug the filter from the electrical outlet and carefully remove it from the back of the aquarium. Be careful not to spill the water in back of the filter.
Dump the water from the back reservoir of the filter into the sink and pull out the filter cartridges. Replace any plugged or damaged filter cartridges.
Unscrew the plastic strainer from the intake tube on the filter. The uptake tube is the part of the filter that hangs down into the aquarium.
Remove any debris stuck in the uptake tube. You can use the flexible brush that came with the filter, or any flexible brush you have around the house.
Rotate the cover for the filter impeller. This cover is on the bottom of the power filter. Move the impeller with your hand until it moves freely, then place the cover back on.
Replace the plastic strainer on the uptake tube, then place the power filter back over the frame of the aquarium. Place the filter cartridges back in the power filter, then fill the back reservoir with water and plug the filter into the electrical outlet.
How to Troubleshoot a Whisper Power Aquarium Filter
The Whisper power filter can be a good choice for any size tank, but it is helpful to know how to fix common problems. A number of issues, including a malfunctioning impeller unit and a blocked intake tube, can prevent the Whisper from working normally. If you notice that the water flow through the unit is restricted, or if your tank is not as clean as it once was, start your troubleshooting with a look at the filter.