If your Internal filter is not working always fully read and check the troubleshooting section within your product instruction manual first.

Important: Disconnect mains electricity supply before handling or attempting maintenance. Always fully read and check the troubleshooting section within your product instruction manual. 

Please open the unit up and inspect the impeller and shaft for any damage or blockages. Is the plastic propeller part attached to the magnet body of the impeller, or has it come apart or split? If the shaft or impeller has snapped or become damaged, this will need to be replaced.
Replacement impellers and shafts are available on our website please click here

If these parts looks fine and there are two rubber grommets fitted on each end of the shaft, or already inside the fittings, then re-assemble the unit.

Is your aquarium filter receiving water? If your filter is not fully submerged and has run dry, this may be the reason why the filter is now not performing.  

If the units power is completely dead, you may find a replacement fuse fixes this issue. 

If you are still unsure why the filter is not working, please feel free to contact our customer service team who will be happy to assist with some additional troubleshooting, replacements or repairs.