I wrote:
We'd be much more interested a few years from now, and after you've added
some stony corals (acropora, etc.). Those are the ones that appear most
sensitive to "water quality" (whatever that might mean), and that are
rumored to benefit most from water changes.

"bo0ger1" .@. wrote on Thu, 30 Nov 2006:
In what way do they benefit from water changes?

Visual appearance (polyp extension) and growth.

Many reef aquarists report that they can visually observe a slow decline of
the daylight polyp extension of their soft and stony corals (in the absense
of water changes), and also that there is an immediate positive response in
the day or so after a water change.

I agree that it is unclear how this relates to ammonia or other nitrogen
levels in those same tanks. But the coral response to water changes is an
obvious and very common effect.

Increase your bioload and your bacteria cell count goes up (there is a
ceiling for this, which is why aquariums can be over stocked).
Why is this so difficult to understand? My bioload is not relevant! As you
increase your bioload your bacteria proliferate!

How can you not see it? You've answered your own question yourself.

To be more precise, the reason we want to know your bioload is to estimate
what the overstocking level IS for your recommended no-water-change approach.

Surely even you can understand that it might be possible that a reef tank with
regular water changes is able to successfully support a HIGHER bioload than
your suggested strategy of no water changes.

The only way to resolve this is to know what, precisely, your bioload is.
Yes we know you claim to be successful with no water changes. Yes we know
you measure your nitrogen compounds. Yes we know your bioload is below your
overstocking level for your tank.

But we don't know WHAT your overstocking level is! Nor whether it is
significantly less than the stocking level in typical successful reef tanks
(that do use water changes).

Does that explain it? In any case, whether you understand our reasons or not,
why are you so reluctant to just answer the simple question? What, exactly,
is your bioload?

Because it doesn't matter. Your bacteria will proliferate in response to
increased bioload (within reason, ANY tank can be over stocked).

And the critical question is that perhaps your no-water-change tank can be
overstocked far earlier than a similar tank that does do regular water changes.

What do you think will happen to your helpful little bacteria if you removed
the majority of there food with each water change? Do you think they will:
A) Starve and start to dye off. Cell count drops
B) Continue to be happy.

Their food comes from the waste products of the fish (and uneaten decomposing
fish food). Those fish are still there, constantly spewing out waste
material. The new water will quickly fill up with bacteria food again, and
there will be minimal impact on the bacterial populations.

What do you think will happen to your bacteria if you took away the
majority of there "food: NH3/NH4, NO2-, NO3-" with each water change?

(Almost) nothing.

All that food will come back into the new water in minimal time.

-- Don
__________________________________________________ _____________________________
Don Geddis http://reef.geddis.org/
A celibate clergy is an especially good idea, because it tends to suppress any
hereditary propensity toward fanaticism. -- Carl Sagan, "Contact"