While I only ever had a few instances of a fish jumping out of a
preform (wifes 1/2 barrel) I certaily don;t want to have it happen
again if possible. They have not shown any signs of trying to jump
out since.

I am in the process of removing the small little preform that is by
the large pond and installing a large preform. I have just modified it
so it has a spillway lip, which is the same distance down as other
preforms (approx 1 1/4" from top edge)..

So how far from the top edge would you feel comfortable with on
filling a preform with fish in it?
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