All fish were top breathing, however, including my
normally bottom dwelling catfish.

Do you have a bottom drain and good water circulation? Are there "dead
pocket" areas? How heavily was your pond stocked? Gravel? My guess
is this was caused by the pond water being turned or stirred. This,
combined with the power loss caused the oxygen level to diminish.

Sorry for your loss.

Jim
Zone 8a - Dallas, Texas
Pond, Veggie Filter, Pond Maintenance & Pond Tour Pics:
http://community.webshots.com/user/dallas75248