"~ jan JJsPond.us" wrote in message
...
It has simply been my experience that in most situations, there is no
need to do frequent
water changes in a pond.

And that obviously works for you (so far). You have mentioned some
problems, but seem convince from whence they came.

Since we know very little about people coming in here, it is best, imo,
to
hold firm to the advice given by the experts at AKCA/KOI USA and those
that
taught the KHA course (PhD Fish Vets). That mantra being: "Frequent
Partial
Water Changes" of 10%/week.

There are exception to every rule. Such as, if you have ammonia showing,
before you do a water change, detox the ammonia, then you can
proceed. ~ jan

~Power to the Porg, Flow On!~

Actually, what that web page you gave me a link to says is this:

"It is considered appropriate to change out from 5 to 10 percent of a
pond's water per week. A small pond (500 gallons or less) should receive
the 10% weekly change out. The 5% change out is appropriate for a large
pond (5000 gallons or more). Any water replaced after a weekly backflush of
a filter system or other maintenance actions should be included as being
part of the weekly change out amount." That page also says "Partial water
change outs can reduce the amount of anything dissolved in the water but
not totally remove it." That, of course, assumes that there is something
undesirable in the water that needs removing/diluting in the first place.

"Considered appropriate". It doesn't say that it is necessary or even
desirable in all cases. And do note also that the 10% rule is recommended
for smaller ponds (500 gallons), not larger ponds. For larger ponds, a 5%
change is recommended. The problems I've had in the past had nothing to do
with the water. The problem I had with the catfish was mitigated by not
feeding it raw food (store-bought shrimp often contains unacceptable levels
of bacteria), and only feeding it dry pellets. Once I switched to dry
catfish pellets (which it eats voraciously), the problem went away. The
paracite problem occurred because I had introduced a plant without first
cleaning it and quarantining/treating it (call it carelessness, if you
want). Oh, and I too have degrees, so I'm not without an academic
background. But enough of the degree waving, ok? It really is a little
silly, if you don't mind me saying so.