Livewell aerator timer operates the pump in cycling On-Off mode. The timer On and Off duration can be set from 10 sec to 30 min. The default is 30 sec On and 3 min Off. The timer can also be set to run the pump at lower speeds. The first 10 seconds the pump always runs at 100% duty to prime the pump and ensure correct water circulation, then power can be dropped to the lower rate (between 10% and 100%) to run the pump at lower speeds for the duration of the On phase.