"bo0ger1" .@. wrote in
m:

One person stated that they change their water because they enjoy
it.

...but they didn't say that they changed their water _only_ because
they enjoy it.

Really? Are you sure about that?

This person changes their water because they "enjoy" doing it:
http://tinyurl.com/y9xveh


Sure, she said that she enjoys water changes.
I enjoy running reactions to make new urethane acrylate oligomers, but I
certainly don't run those reactions _only_ because I enjoy them (if you
asked my employer; my enjoyment is pretty low down on the list of reasons
why reactions are run ;-) Its the difference between citing _a_ reason,
and citing _the only_ reason... Do you understand that difference?

I was of course referring to Wayne's article at his site,
and its reflection on _his_ grasp of the nitrogen cycle.

His "grasp" of the nitrogen cycle? He doesn't even now what ammonia
or nitrite. How could he possibly understand the nitrogen cycle when
he doesn't even understand the basics?


Simple. Chemical reaction notation is nothing more than short-hand, a
condensed "language" to communicate ideas that would otherwise take longer
to express in written words. Lack of competency with the notation doesn't
imply a lack of understanding of the underlying concepts. Wayne's grasp of
the nitrogen cycle is as comprehensive as any you've cited as necessary for
understanding. His Chemical notation needs some work, though.

Are Wayne's errors with chemical notation the only thing you can offer as
supporting your assertion that most NG participants don't understand the
nitrogen cycle?

Also, you replied without saying anything to support your assertion
that the forum users here 1) are changing water because everybody
else is, and 2) that they lack sufficient understanding of the
chemical and biological processes in their aquaria. Again, what has
convinced you of that?

This newsgroup.


Asking for specifics, and getting broad generalizaions... What,
specifically, posted in this newsgroup, has convinced you of that?

New values for you:
OR is it my pH which is 8.1-8.2? Or is it my salinity which is 1.024?
Or is it my lighting which is 4 110watt VHO's?

BTW. If you haven't tested
your water recently, who's to know whether your nitrates are up, and
your fish and anemone just don't show it, because its been developing
slowly since your last test?

I test once a month.

I thought you "used to" check water parameters regularly..? It sounds now
like you've been testing regularly all along. That's great, as it would
give continuity to your observations, but its also a little troubling, in
that it conflicts with your previous comment.

Not only am I convinced that most in this NG don't understand the
above (N2 cycle and denitrification), I am NOT convinced YOU
understand based on your questions.

This is why MOST do water changes. Because they DON'T understand at
the biological level why it is NOT necessary.


....and what, then, is the reason why those who _do_ understand aquaria at
the biological level _continue_ to advocate the use of water changes?
Here, I'm thinking of published marine biologists such as Delbeek, Sprung,
et al. Their grasp of the topic outstrips mine, yours, and everyone
elses' on this NG, and yet they advocate WC in reef aquaria.

MOST think that the ONLY way waste is removed from their aquarium is
by doing water changes.

No, they don't. Most people here understand that the live rock/sand and a
protein skimmer (or other filtration) do the majority of the "heavy
lifting" of filtration and nutrient export, and that small regular water
changes are a final (important) step in maintaining water quality.

This is a HUGE fallacy!!

Or, its a little strawman...


1-hermit crab. A few snails.

Pretty small crew, for a 75gal...

Why do you say this? What information have I given you to make you
come to this conclusion? Was it my excellent water parameters?


That wasn't a judgement, it was merely an observation. 1 hermit and a few
snails in 75G is a small cleanup crew. *shrug*

Again. I am pretty sure we have been through this already. Ammonia
--- nitrite----nitrate----N2(g) + H2O. (Enzymatic conditions via
bacteria.)

They go a little further, though, and also take account of the fact
that
there is a maximum possible population of bacteria for a given tank
setup,

Sure there is. This is why it is possible to over stock an aquarium
with inhabitants. NOT the reason to do a WC.


What is the over-stocking level for an aquarium using NWC? Is it any
different than one using WCs? Not knowing the clear answer to that last
question, I'd probably accept a quantification of your bio-load as
sufficient information to proceed with trying NWC, if that bio-load
approximates (or is greater than) my own.

a relationship between fish species/mass and the amount of waste
generated,
and differences in final water quality depending upon the details of
the above, and that certain aquatic species (especially corals) are
intolerant of less-than-perfect water quality.

Which of my water parameters are "less-than-perfect"?


None, to the extent you've described them, for your bio-load. What was
your bio-load, again?

Doing water changes guarantees "perfect" water?


There are no guarantees of perfect water, but WC's are the most researched
and supported method for maintaining the kind of water quality that results
in successful reef aquaria.

And really, you haven't shown them to be "unnecessary".

You haven't shown that they are "necessary". Nor has anyone else.


In the absence of supplementation, water changes are necessary. You
yourself dose monthly with Kent Merine Essential Elements.

What you've suggested is that Kent Marine Essentials can
supplant/replace their
necessity in a FOWLR system of some unquantified setup. Blackhole
has a similar method for a reef setup, which adds a nurtrient export
method (that you discount without elaboration),

I haven't described my nutrient export method?

Yet another Non-sequitur. Sure, you've said your bacteria do it all.
But then, you discount Blackholes nutrient export system (bo0ger1: "not
necessary IMHO") without further elaboration. If you'd care to elaborate
on why nutrient export is "not necessary IMHO", feel free. If not, we'll
value the comment for what it is.

My experience tells me that there is an upper limit to the load you
can place upon the bacterial colony in a tank.

How many experiments have you performed?

I've maintained five different marine setups by this point in time,
snip tank descrip.
That was your experiment for this:
"My experience tells me that there is an upper limit to the load you
can place upon the bacterial colony in a tank."

What you described weakly qualifies as an experiment.

Its nothing of the sort. Its anecdotal information. I posted in reply to
your request for experiments to elaborate on my _lack_ of experience (five
anecdotal data points. Whoopie! That amounts to almost nothing), not the
extent of my "formal investigations", as explained at the end of the tank
description. I'll duplicate those comments here, since you seem to have
missed its significance:

boo0ger: "Is this anecdotal data? "

atomweaver: "*It sure is*. There's nothing wrong with that, per se, so
long as any readers value such information appropriately, and so long as I
don't get a swelled head, or start ragging on others for acheiving success
differently..."

In this light, your side-track about scientific method is very obviously
mis-placed, as I myself don't ascribe any great degree of _scientific_
value to my results (or yours, or anyone elses anecdotal data, for that
matter). Personal experience certainly has value (humans get along in a
range of purusits _fantastically_ by relating personal experience,
including the keeping of aquaria) but it isn't science. Context becomes
vastly more important in those instances where the controls of the
scientific method are absent.

How does your
"experiment" quantify bioload?
When do you address and quantify the
"limit"?
Where do you mention your control tank with NO water changes? And
what was the "upper limit" of bioload that you placed on your bacteria
in your control tank?
What was the "upper limit" of bioload that you placed on your bacteria
in your WC tank?

My comments aren't designed to answer any of these questions directly,
but rather to offer context to my meager anecdotal data. If you take the
information given, and add to it the mass of the fish and inverts involved
(5.5 inches BL of Banggai, 4 inches of blenny, 5 inches of Clown wrasse,
and 4-5 inches of length to each clam along the sissal opening, 3 inch dia.
open brain, 5 inch dia leather, 9 to 10 inches irregular diameter green mat
zoanthid-covered rock), a reader gets pretty much a clear picture of my
bio-load, which I think is relatively low, vs. what I've seen/read about in
other systems this same size. But that's OK, the system is relatively new
still, and I'm a relatively inexperienced marine aquarist, especially wrt
corals. I'll continue to err on the side of caution until my experience
warrants otherwise...

As I said, I would relate the results of the rest of those tanks in
another thread, but as they have nothing to do with bio-load under NWC, its
a topic I didn't elaborate on here.

How many conditions have you varied?
Different fish, different bio loads, mostly the same live rock (I
like my Fiji rock, its got high porosity for its weight, and I think
that gives me a better living filter). I'd be happy to chronicle the
past experiences, but that would be more appropriate for a different
thread. The conclusion of them is that, the need for water changes
and their degree varies, based on occupancy and the water quality
demands of the specific species.

Is this anecdotal data?

It sure is. There's nothing wrong with that, per se, so long as any
readers value such information appropriately, and so long as I don't
get a swelled head, or start ragging on others for acheiving success
differently...

Why is my/others NWC anecdotal data less valid?


Because it lacks context. If you're going to offer anecdotal data in
support of NWC, it is at its most valuable when used by other systems which
approximate the context within which success was achieved. In the abscence
of a scientific study on NWC, I can have a greater degree of confidence in
reproducing your results, the closer I am to the system within which you
achieved success.


Thanks to others for adding their comments on the bio-load discussions, I
removed most of that discussion from my reply, as Don and Rock have taken
up the topic well. Bo0ger, I understand what you're saying about pulling
nutrients out by (basically) diluting them in the water column, but most of
your comments thus far imply that the water column is the primary means by
which the bacteria obtain their nitrogen. I was under the impression that
fish and invert waste arrived at nitration sites both from the water
column, _and_ by the decomposition of settled waste in direct contact with
the substrate and LR (marine "mulm" decomposition, to borrow the FW term)
which WCs only affect indirectly. Some questions for all; Is my
understanding of this incorrect? If not, what is the relative contribution
of both means of delivery of nutrients to the bacterial colony?

Another question on the topic of bio-load; time. Anyone have an idea
of what is the response time of bacteria to a change in nutrient
availability? Anyone have an idea of the "cycle time" in the nitrogen
cycle?

Regards,
DZ
AW

(I'll be sporadic in replies for the rest of the year. "Life" rears its
ugly head, in that Not-Good kind of way.)