koi making mess in pond

We have large kidney shaped pond in the country. We were told the koi
would clean up the greens. Well the pond is so muddy that we can't
even see the fish. 5 of our 22 inch bass died last year. They were
like our kids pets and anyone fishing enjoyed catching them. I think
it through the oxygen levels off and being so muddy they couldn't find
food. My opinion. The bass are out and we would like to have the gold
carp instead. Saw a pond full of them and so much fun to watch.

We feed them in the same place every day but when you put a net in
there they disappear and are spooky for a few days.

How can we trap those koi. They are huge and much bigger than the bass
we had. Is there a plan that shows how to make a trap? We have
someone who wants the fish for an over grown pond.

Thanks,
Evie