If your Reefsurge-4000 or 8000 stops working but the controller is still lighting up you will need to restart the controller. To do this follow the guide below;
 
1. Important: Disconnect mains electricity supply before handling or attempting maintenance. Always fully read and check the troubleshooting section within your product instruction manual. 
 
2. Wait 1 hour then re-plug the unit and connect all power cables.
 
3. This will restart the controller and restart the pump.
 
If your unit is still not working please contact us our customer services team who will be happy to advise further.