Tadpole, I experienced a few variables because of Sandy.....first the extreme winds blew a lot of water out of the pond. The level went down about 4" and the pond is 16 X 12.
Then we got rain, rain, rain in fact it overflowed the edges.
But after all the wind & rain, the pond leveled out and the fish were fine. They ate as normal and we didn't lose one.
Mind you, these are not "koi" but gold fish that I bought 3 years ago. They have grow from 1" to over 8" and look like koi to everybody that comes buy to look.....LOL