Need feedback on this paper

I am going to print your response, is very interesting and a good learning
experience.

I haven't post new data on my website, I've been a little busy but for the
past months, the level of nitrates fluctuate around 50mg/L and PO4 are about
0.25mg/L

I don't have enough time to answer every one of your remarks. There are
other more open-minded posts that are keeping me busy.


"Pszemol" wrote in message
...
"Guayni; SAHS" wrote in message
...
Over the years, I've found a great amount of information regarding the
role
that nitrates (NO3-) play in sal****er systems. The majority of the
information available tends to be confusing and inconclusive with
respects
to the level of danger this compound represents to a healthy sal****er
aquarium. Much of this information characterize nitrates as a toxic,
unwanted and dangerous compound that should be brought down to zero in
most
cases and recommends to the fact that "high" levels of nitrates are
extremely dangerous to the fish.

Jaime, could you produce any examples of such information about reef
tanks?
I am reading hobbyist literature for years and did not find ONE
which states that nitrates are "extremely dangerous" to the fish...

What I read frequently is that elevated nitrates are causing
nuisance algae blooms, which are not tolerated in reef tanks.

While I agree with this basic assumption,
the information that follows will clarify some facts regarding this
compound
and represents it as an unwanted byproduct of a healthy system that
should
be kept to a minimum but should not be a catalyst of drastic actions.

Thes is nothing different than what can by read in hobbyist literature.

Where do nitrates come from?

Nitrogen enters your system in one of two ways. The first and most
important is in the form of food you give to your fish. The second and
extremely less important is by gaseous exchange between water and air.
The
latter is very hard to achieve and could be considered negligible to our
analysis.

Well, in a fish tank overrun by cyanobacteria this way of nitrogen
intake seems to be quite significant. Do you have any scientific
data to back up the claim this way of nitrogen intake is negligible?

Once the nitrogen cycle has changed nitrites to nitrates it enters the
food
chain. The nitrates are very useful compounds for plants. It is here
that
the Nitrogen Cycle fails in the aquarium. Nitrates are supposed to be
absorbed by plants and turned into animal matter by herbivores which in
turn
get utilized by carnivores completing the food chain and starting the
cycle
ones again.

Most healthy reef tanks create closed circle of nitrogen already
by utilizing algae scrubers, lit refugiums with tons of macroalgae
and this biomass is exported by mechanical harvesting of algae.

Are high amounts of nitrates a sign that the nitrogen "cycle" isn't
working?

The answer to this question is no if; the levels of ammonia and nitrites
are
at or near zero. What this mean is that your nitrifying bacteria is
working
by oxidizing first ammonia and then the nitrites. The toxicity of
nitrates
is not an immediate menace to your tank and can be removed from your
system.

This makes no sense at all. The question was "are high nitrates a sing?"
and your answer was "no, if the levels are low". How silly is that?

I would suggest a better indicator of the not working nitrogen cycle:
If nitrates level IS RISING than your cicle is not fully closed...
It simply means that nitrogen intake is not balanced with nitrogen export.

The following figure exemplifies the nitrogen "highway" in your tank;

Figure 1 Nitrogen Cycle in your tank. As you can see, nitrogen is not
recycled but has an input and an output. The preferred output is the
harvest of plants but the most common known output is by means of water
changes.

Is this article posted on your website http://www.guayni.com?
Figures are not visible here.
By the way - I visited your website and I cannot find the table with
the data from the NO3/PO4 measurements in your tank... The values
I remember from my last visit were at or above 100mg/l. How is the
situation now? Can you post some current readings or current tank photos?

In the previous diagram (Figure 1) it is also seen that when
nitrates are absorbed by the herbivores in your tank, they don't get
extracted, they are returned to the tank in the form of excrement which
contains lots of toxic ammonia. Algae eating organisms can incorporate a
certain amount of nitrates but not enough, the surplus is sent back to
your
system. Alright, they may help you keep the tank pretty but also
contribute
to increasing the amounts of ammonia in your system. This may come as a
shock to many aquarists under the impression that snails and blennies
were a
good way to control algae in your tank. But, as I show in figure 1, they
augment the accumulation of ammonia thus the levels of nitrites and
nitrates.

Here is a flaw in your reasoning:
Snails and blennies cannot contribute to the nitrogen intake since
they do not acquire nitrogen from the outside of the tank...
They just process nitrogen which is already in the tank and use it
partially to build their body tissues and produce eggs/fry which can
be consumed in turn by other fish and corals in the tank...
Effectively they HELP lower down nitrates by incorporating it in
their bodies.

In a healthy aquarium an aquarist should ensure that the
amount
of ammonia and nitrites are kept at or near zero. This will confirm that
the part of the nitrogen cycle that takes place inside your tank is
working.
Now we have the difficult task of removing the unwanted nitrates. If the
levels of nitrates reach a certain level, your nitrifyers aren't able to
turn nitrites to nitrates do to saturation. This starts a chain reaction
where the nitrites reach a level of saturation that will kill your
organisms
and then your nitrosifyers can't convert ammonia to nitrites. When this
happens you no longer have a system. At this moment, high levels of
nitrites will have destroyed the organisms in your tank.

What is the saturation level of nitrates in the sal****er expressed in
mg/l?

What is a sustainable level of nitrates in an aquarium?

Let's make something clear, nitrates are toxic and they should
be kept as low as possible.

Did not you said at the beginnig of your wire up that similar claims made
in hobbyist literature are "confusing"? You do not say anything different.

Any conventional aquarist will recommend a
series of water changes to reduce or eliminate nitrates.

This is the fastest, cheapest and easiest method of dealing with
excess of nitrates when long term solution is not in place yet.
If you have a reef tank poluted with 100mg/l of nitrates there
is no other method of bringing nitrates down to 5mg/l faster
and cheaper than a water change. When your nitrates are brought
down to 5mg/l then you can work on a long term solution and
balancing nitrogen intake with nitrogen export...

Other than that,
they will refer you to buy nitrate reducing chemicals. I have a
different
approach. In many scientific papers is mentioned that nitrates are toxic
at
levels near 100 milligrams per liter, one paper says that at a level of
1,000 milligrams per liter it will cause the death of your fish. I
recommend a level of less than 50 milligrams per liter although my tanks
had
remained near 70 for a prolonged time with no drastic effects to my fish.

Could you post a healthy looking reef tank pictures with
long term exposure to nitrates levels ranging 50-70mg/l?
I would risk a statement such pictures will be impossible to find.

The best way to remove nitrates is to know the carrying
capacity
of your tank. What this means is to have the knowledge of how many fish
and
other organisms your tank can support before nitrates become a nuisance.
Another great thing to know is the amount of food your fish need daily.
If
you can control the intake of nitrogen (food), you've won the first
battle
against nitrates. Should you want to increase the number of fish in your
tank then you have to implement my approach. By growing plants in your
tank
and harvesting them regularly you are not only creating a better
environment
in your tank, you are also extracting living material that contains
nitrogen
absorbed from the water by these plants, NITRATES. Not only are you
removing nitrogen from your system but also phosphates and other toxic
compounds that are absorbed by these plants. I check my parameters
biweekly, in order to have a controlled system, the amount of plants
removed
must match the amount of food added.

What you just said is nothing revolutionary. It is practiced FOR YEARS
by many hobbyists keeping beautiful reef tanks with low nitrates...

To conclude this paper I will like to summarize my findings by
mentioning key aspects of a healthy sal****er aquarium;



Ø The level of ammonia should be kept at or near zero

o This means that your nitrosifyers are doing fine

Done with no problems in any tank.

Ø The level of nitrites should also be kept at or near zero

o This means that your nitrifyers are doing fine

Done with no problems in any tank.

Ø The level of nitrates should be kept to less than 50 milligrams
per liter

o This means that there is room for your nitrifyers to work

Done with no problems in any tank.

Ø Feed as less food as possible to your fish

How to prevent malnutrition of fish or starvation with this advice?

Ø Grow as much algae and other plants in your tank

Plants make water yellow... How to deal with this issue?

Ø When doing water changes, keep it to small amounts (10%)

What is the purpose of 10% water change and how often should I do it?

Ø Don't overcrowd your tank with fish

How practicaly can you tell the tank is overcrowded or not?

Ø Remember, keeping low levels of ammonia and nitrites is more
important than lowering the levels of nitrates

Who has problems with elevated levels of ammonia/nitrites in their mature
tanks?
This problem DOES NOT EXIST!

I hope this paper is useful to new aquarists and maybe to
advanced ones who didn't understand or were misguided on this complicated
cycle. Many local fish stores (LFS) will completely disagree with my
views
but that is expected. They make lots of money by selling pre-mixed
sal****er, chemicals and other quick fix solutions to the nitrates
problem.
Some even portrait nitrates as the real menace to your tank and scare
clients to a point that they invest thousands of dollars in their
gadgets.
It is a win/win situation for them and a severe loss to the aquarist. If
you have to do water changes more than once every six months (some even
weekly): you can toss all your gadgets away because they are not working.

Once again: what purpose does 10% water change every 6 months serve?

Yours truly;

Jaime Rivera Sierra, who was trying to patent and sell expenssive gizmo
filter for our tanks and posted about this filter here on this group
not so long time ago :-) Check out what he wrote in the past:
http://groups.google.com/group/rec.a...3482dfe1c4abd0
http://groups.google.com/group/rec.a...50df0777f9095e
His "experience" is with one fish-only tank, 7 fish (not reef) and this is
his
whole fish tank keeping experience. His tank is full of ugly algae and
very high nitrates @ 100mg/l. He claims to be in possition to paten a
magical
filter (gizmo?) which lets you avoid water changes at all...