Jeff, it would be hard to imagine that any fish could survive a trip through a centrifugal pump, but I guess it could happen. However, I would guess that fertile eggs would be a little more likely to survive.
I can't speak from experience on filtering, as I haven't used a filter yet. I will tell you what I have set up for emergencies, and I hope it gives you some ideas.
My approach is to use a gravel filter bed. I will pump water from the source up to a grassy lane. The water will run about 800ft through grass. It will only run 1"-2" deep and 6' wide. The water will eventually reach my filter, and be filter through about 3-4' of limestone gravel as it enters the pond. I hope I never need to actually use it. If I do get a big dry spell and am forced to use it, I feel pretty good about it. I think 800' of grass and 3-4' of gravel make a pretty good filter.
