Lets see if I can answer this correctly but before I try remember the search mode also very important the upper threads hold a file called Frequently Asked Questions and a search there will get you good info on Livewells like this Proper Livewell use – Spring Update on How To Ok back to your question When the valve is open gravity will allow the water to drain from the livewell with the boat in or out of the water (some water may enter the livewell or not drain while in the boat is in the water) The aireator pump will pump water in when the valve is open or closed if the boat is in the water, when the valve is open boat in the water and the aireator is on it will more than likely fill the livewells a little over half way but when you take off the water will be sucked out. When the valve is closed no water should drain from the livewells whether you are in the water or out.
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