Need Alittle More Info, Does It Have A Float? Or Is It On A Timer?

If It Has A Float, Sound's Like You Need To Adjust It To Turn Off Sooner.

If It Is On A Timer, You Push The Tab's Out For On & They Will Be In For Off, The Timer's Also Have On & Timer Switch, If It's On The Outlet Is Live, If It Is On The Timer Side Then The Timer Tap's Run The On & Off.

Hope That Help's, If Not Take Some Picture Of The Pump & Or The Timer So We Can See What You Are Working With.

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