need help to identify eggs in pond

Hello, one of my 13" koi has been looking pretty fat in the belly area.
For the last
24-36 hrs one of the other koi has been following nudging this one fat koi.
My question is, do the koi lay live fish or eggs? The reason is that
there are
a thousand 1/16" eggs stuck to my plants, pumps, some rocks and I was
wondering
what the deal was. I also have 4, 5-6" pond comets in this 700 gallon pond.
Can anyone hazard a guess?
Thanks for any info.
Oh, the fish seem to be hanging right near where the waterfall cascades on
the rocks, all side by side and facing the falls. Are they there because
I have low oxygen?
A 1/4 water change didn't seem to make a diff.
Bruce
ps, remove SPAMNOT to reply off list.