Alright, I've had several requests for photos of my duck pen set-up and plastic duck pool. So here they are. You can also see a video here. (New Photos Added: See Page 6 of This Thread) At any rate, the duck pool is a 30 gallon mortar mixing tub which I purchased at Home Depot. I drilled a hole (about 1 inch in diameter) into the bottom of the tub and then attached a kitchen sink drain where the hole was drilled. I sealed the drain to the tub with silicon gel (the same type used for sealing panes of aquarium glass). This keeps the drain from leaking around the seal. To the bottom side of the sink drain I attached a PVC adapter and PVC pipe. The pipe runs under the pen and through a piece of deck board that is attached to the back side of the pen. This supports the weight of the PVC pipe and gives it stability. I have attached a PVC ball valve to the end of the PVC pipe. This allows me to drain all the dirty water in the pool by simply turning the PVC ball valve to "on". Then I turn it back off, I refill with clean water. All PVC parts and joints have been sealed with PVC cement. With this set-up, I have eliminated the need to ever dump out dirty tub water... instead, I just turn a switch and the dirty water automatically drains out! On a side note, I will eventually be painting the house portion of the pen barn red to match the adjacent chicken house. I will also be painting the roof black and covering it with black roofing shingles. The PVC pipe and wood support brace will also be painted black to match the tub/pool. I will eventually be building another pen exclusively for the mandarins. It will be similar in design. However, it will include a larger "pond" consisting of an 80-100 gallon stock tank. The house portion will be two story, with the upper story consisting of four private nest boxes. The lower story will be a communal area where the feed will be offered.