Thanks for your comments on my draft, they are very helpful!
The language had to be kept at a very low level, using proper biochemistry
nomenclature would had been confusing for many. I haven't seen a NO3 test
kit using NO3- or NO2 used as NO2-.

Also, thanks for mentioning the N2, I did miss that one, thanks again.

"Booger" .@. wrote in message
...
Every living organism incorporates nitrogen to each and every cell for
many reasons. The amount of nitrogen not needed for flesh is excreted
back to the water in the form of ammonia.

Nitrogen needed for flesh? By this do you mean nitrogen that is needed to
biosynthesize amino acids for protein synthesis?

Once Ammonia enters the water column either evaporates as
ammonia gas (NH4+)

Ammonia gas is not NH4+ it is NH3. Ammonia gas does not evaporate because
it is already a gas. Only liquids evaporate.

or gets recycled in the nitrogen cycle. This task is performed by
nitrifying bacteria that turns ammonia (NH3) to nitrites (NO2).

NO2- not NO2

In the nitrite form, N stays unstable replacing oxygen in breathing and
affecting in many ways the metabolism of your fish.

What do you mean by "unstable" here?

The nitrifying bacteria continue to process
nitrogen-containing compounds turning nitrites to nitrates (NO3).

NO3- not NO3

At this point nitrogen is at its lowest unstable condition becoming
accessible to plants. In the nitrate form, algae and other plants
reincorporate nitrogen into its tissue.

By this you mean they use it to biosynthesize amino acids and proteins,
right?

An excess accumulation of nitrates may cause some problems to your system
as it remains unstable. NO3 can't be reduced again by nitrifying
bacteria and has to be removed from the tank.

Reduced again? What do you mean by this? Nitrate is the highest
oxidative state of nitrogen.

There are different methods to achieve this task. The most common
procedure is known as a "water change". Using this technique, aquarists
remove water from the tank and replace it with waters with low nitrates
levels, thus diluting the water column. This method is costly and tedious
requiring periodical water changes that may range from twice a year to
twice a week and from 10% to 20% of the water column. Another good method
of extracting nitrates from the water is by harvesting plants that
incorporated nitrates to its tissue. Since under this conditions N is not
a limiting nutrient, plants will bloom and algae will cover your tank
making it easy to remove. The more plants you harvest, the less need for
periodical water changes. Each plant you extract contains nitrogen built
into its living tissue from the most available source, NO3.

Are there not anaerobic bacteria that metabolize nitrate into N2 and H2O?
Why did you leave this out?


In summary, nitrogen is an element that needs to be controlled in your
system. The nitrogen cycle works only one way. The nitrogen in your
system enters in the form of food, this food is taken by your fish and
the excess is redirected to the water column in the form of ammonia.
Nitrifying bacteria turns ammonia to nitrites and then to nitrates. Once
the nitrogen is in the form of nitrates the only way out is mechanical.
An aquarist has to make a decision to extract nitrates directly from the
water by means of water changes or by harvesting plants that utilized
nitrates as nutrient.



References;



Dakin, N. 2003. Complete Encyclopedia of the Sal****er Aquarium



Mitsch, W.J. and J.G. Gosselink. 2000. Wetlands 3rd Ed.



Rivera-Sierra, J. 1992. Impacto Ambiental Acumulativo Del Desarrollo
Costanero En El Sector Playita De Salinas, Puerto Rico






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