Self draining duck pen? Is it possible?

[jcnpearce]

I also bought a dirty water dump pump of amazon for 70$ to drain the pond and the tub in the coop as needed. I'm hooking a garden hose to the outtake valve and using it around the yard and in the veggie garden. Would have used the water anyways on all the plants so at least now it's packed with poo fertilizer

 

[jcnpearce]

I should also mention these are established plants. I would think if its young and just starting they may eat it. You might get a plant going in a small stock tank or something like that and once its large enough put it in the pond