Rob,...they have built in timers,...once you set your livewell controls to "Auto", it'll run for a few minutes then shut itself off, and then restart a few minutes later (i don't know what the exact time is...maybe every 5-7 minutes)....manual will run constantly until you shut if off. The beauty of the "Auto" setting is simple,,......turn it on and forget about it......it'll keep the water in the livewell while you're fishing and running,....and when you stop and come off plane,...it'll re-fill your livewells automatically to compensate for the water that ran out the overflow valve, while you were running....just put it on "Auto" and get back to fishing!! LOL....also check the "Flow-rite" link in the "links" section on this site,...it'll explain all the valve settings and answer all of your livewell control FAQ's!!
Good luck,...hope this helps!!
Regards,
Mac
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