Your aquaclear power filter has stopped working?

It's possible the impellor is gunked up and the motor froze. Remove the black motor portion from the plastic container. Gently pull the impellor out and clean with an old toothbrush, try using one or two Q-Tips to clean the channel where the impellor spins, be careful not to damage the guide pin. Reassemble everything and try using the power filter in water, filter should never ever be used without water. If you don't hear any noise from the motor, try tapping on the motor housing to unfreeze the motor, it that doesn't work, it's time to purchase a new power filter.