I have a 2" trash pump rated for 168 gals/min. I'm not at the property long enough to run that for enough consecutive days and hours to succeed. If I was, that would be great, but unfortunately no. I need to start a siphon, then come back a few days later when it is hopefully done.

I am comfortable with my siphon setup except one issue. When I have the discharge capped, pouring water in the tee at the top, it seems it would run down the intake to the pond and just keep going. Won't the water level inside the pipe want to be the same level as the pond since I have the cap at the top open?

I can try this, but it seems I need a shutoff on the intake so I can fill that with water without it running out as fast as I put it in?