Thank you everyone. Looks like gill parasites are the one to look for.
Appreciate all the help.

Gary
" George" wrote in message
news:QbVne.8623$_o.5075@attbi_s71...

"gng" wrote in message
...
It's not oxygen. I have a Sequence 7200 with a nice, full waterfall and
none of the other fish are doing this. Tons of water coming off the
waterfall, in fact. What I did not tell you was that this fish has some
odd
tumors growing on him that the koi store said were sunburn - and that
short
of surgery, there was nothing I could do. Pond is actually very healthy
with crystal clear water and 20% water changes every week. I could toss
some Paraside Green into the pond to clear out any parasites.... good
idea?

You have a 2500 gallon pond and you do 20% water changes every week?
Dude,
that is overkill, to say the least. Unless you have a specific problem
with your water, such as high nutrient levels or toxins in the water, I
fail to see the advantage of 20% water changes weekly. I'd hate to have
your water bill. If your fish has tumours, then obviously there is
something wrong with it. Whether those tumours are causing the problem
you
describe is debatable. I would check for gill parasites.