I have a secure house for mine as well :). I am now worried about my ducks during the day after hearing that coons can climb :(. I am probably over-reacting though if coons are nocturnal.
Wow I never knew racoons could climb fences. Racoons are nocturnal though right? So if the ducks are put in a duck house a night they should be safe from racoons?
I am so sorry for your loss :(. If you decide to get ducks again, a predator proof pen is:
5 foot high fencing, and put 2 feet high hardwire cloth around the bottom of the fencing. Have strong netting over top, and concrete slabs going all around the outside of the pen.