I understand, Andrew. And I prefer to keep the O2 in my water at saturation,
not "less than". A spray bar on the water return to your pond would help
with the pond's O2 levels; the spray bar to your filter is excellent for
keeping the biobugs happy, but may not do too much for the fish once the
water gets back to the pond. Even the folks running the Nexus filters - who
positively BOIL the filter media with air - still run supplemental aeration
in the pond itself. However, if you have a low stocking rate, you won't need
additional aeration at all. It's just that most of us push the envelop, if
not down-right STUFF it. All fish benefit from O2 saturation. It's just that
most don't get it. For instance, well water has almost NO oxygen, and it
must be introduced via degassing. Water from the tap is low in O2 after it's
been pushed through miles of pipe. Further (at least in my instance), if
your area is subject to power outages, if the water is at O2 saturation,
your fish will not get into distress as rapidly as they would if
supplemental aeration had not been used.

I'm really not trying to twist anyone's arm he as in most things, if you
don't like it and don't want it, don't use it. No big deal (except maybe to
the fish). But if your pond is lightly stocked, it's not as important.

Lee

"Andrew Burgess" wrote in message
...
"Lee Brouillet" writes:

I must (respectfully) disagree with you on this, Sam. By the time the
fish
are hanging out on the surface or at the waterfall, they're STARVED for
oxygen, which is nearly too late. Why wait that long? They will grow
better
and be much happier with adequate O2 in the water. Mother Nature pulls a
dirty trick on fish: in the summer, when they're the most active and
growing, she yanks the oxygen out of the water because it's warm. Think
of
it like trying to run a marathon in Denver without training for it . . .
sorry, there's just not much O2 in the air up there G. Same thing: not
much O2 in warm water. Aeration is like filtration: you can't get too
much.

There is a saturation point for oxygen dissolving in water.

For filtration I agree, just because if its twice as big it needs to be
cleaned
half as often.