I recently changed my holding water pail from 2 gal to a 15 gallon pail. I have the pump at the bottom and the hose rising up 3 feet above the top of the pail and then it routs back into the sump. My problem is when the pump shuts off the water keeps siphoning through the pump. I thought the hight and bend in the hose would break the siphon. I have no problems when using the smaller volume of water (pail). Any ideas how I can resolve this. It looks something like this.