INTRODUCTION:Nitrogen is an element vital to all life processes on Earth.
Nitrogen is very important in our biosphere, where nitrogen comprises 78% of the
atmosphere, and is part of every living tissue. It is a component of amino
acids, proteins and nucleic acids. With the exception of carbon, nitrogen is the
most universal element of life. Life could not exist without nitrogen. Nitrogen
is essential for organic development; nitrogenous compounds are also required by
some organisms for metabolic functions and respiration.All living organisms,
from fish to plants, have great quantities of assimilated nitrogen in their
tissues. Nitrogen is a fundamental ingredient for the formation of proteins and
nucleic acids. Every organism you place in your aquarium adds nitrogen; from
fish to coral, to live rock, to plants. The introduction of food also adds
nitrogen. Dead or alive, they are organic masses, and possess the same
nitrogenous attributes as the fish, plants, invertebrates you added to your
aquarium. Inorganic nitrogen is added two ways: the atmosphere and new water.
Atmospheric nitrogen (N2) is incorporated into our aquarium water by way of
nitrogen fixing bacteria and by cyanobacteria as ammonia (NH3). Inorganic
nitrogenous compounds from our tap or well water also enter our aquarium, often
as Nitrates or Nitrates. Reverse Osmosis can remove much of
this.NITRIFICATION:When an organism dies, nitrogen is moved from plant or animal
into the inorganic chemical ammonia by the process of bacterial decay. Ammonia
is also produced by bacteria in the breakdown of protein. This process is called
Mineralization and is the end result of the metabolism of food. However, ammonia
is produced from both metabolism and mineralization. The decomposition
(mineralization) process produces large quantities of ammonia (NH3) through the
process of ammoniafication. Heterotrophic microbes utilize the organic compounds
of decomposing matter as their carbon source. Ammonia (NH3) is the byproduct of
this consumption. Ammonia, in its neutral state, exists as ammonium
(NH4+).Ammonia (NH4) is assimilated in more than one way. Plants (such as
Hornwort) and algae can assimilate ammonia and ammonium directly for the
biosynthesis. The remaining bulk of decomposed byproducts are utilized by
bacteria in a process called nitrification. Ammonia does not last long in a
healthy aquarium environment, fortunately. Nitrifying bacteria such as
Nitrosomonas quickly break down ammonia into less toxic Nitrite (NO2). During
this process, specific species of nitrifying bacteria strip the ammonium of its
hydrogen molecules as an energy source. Oxygen molecules are then affixed to the
stripped nitrogen, forming the oxide nitrite (NO2). Another group of bacteria
(Nitrobacter ) utilize the enzyme nitrite oxidase that is then responsible for
converting nitrite into nitrate (NO3). This nitrate can either be used by plants
as a nutrient source, or can be further broken down into nitrogen gas (N2)
through the activity of anaerobic bacteria such as Pseudomonas .It should be
noted, that without oxygen (nitrification is an oxidative process), none of this
process can take place. It should also be noted that in recent studies the
Nitrosomonas and Nitrobacter responsible Freshwater nitrification are NOT the
same in saltwater.BIOFILTRATION:Nature can pack a lot of bacteria into small
places, which is to the advantage of the aquarist. For bacterial growth, all
that is required is ammonia and oxygenated water. This is the beginning of the
nitrogen process and the growth of bacterial colonies. Remember you need oxygen
and a lot of surface area for bacterial colonies. Wet/dry filters, sponge
filters, ceramic media, and loosely packed upper layers of gravel are all
sources for bacterial accumulation. If there is not adequate surface area in
oxygen areas of the filter media or gravel, nitrification will be poor. Water
will follow the path of least resistance, so if your filter or gravel has a
build-up of non-nitrifying bacterial slime or is packed to tightly,
nitrification will not be achieved. Sponge Filters or Pre-Filters are an
inexpensive filter medium for colonies of nitrifying bacteria. Wet/dry filters
and live rock (in Marine Aquariums) are excellent sources of bio filtration in
larger aquaria. Bio-Wheels are very popular, but in my tests in my maintenance
business they are VASTLY overrated. They tend to accumulate hard water deposits
and stop and even when they are working my tests have shown little difference in
aquariums when they are removed as compared to sponge filters or wet/dry
filters. Canister filters are also good sources for nitrification as long as the
proper media is used (such as ceramic rings) and the media is not packed too
tight and is rinsed regularly.DENITRIFICATION:Is the process of converting
Nitrates (NO3) in to Nitrogen (N2), which is dispersed into the atmosphere. This
process can take place in an environment without oxygen by anaerobic bacteria.
This process is more common in Marine aquaria and takes place in fine #00 sand,
, live rock, or ?aquarium mud?. In freshwater aquariums this process often
produces deadly Hydrogen Sulfide, but by maintaining an oxygen level above 1
ppm, this can be avoided. Plants roots are great for maintaining this balance of
oxygen in the gravel for proper Nitrate removal A thicker layer of coarse gravel
utilizing a "void space" called a plenum is often used for Nitrate removal in
Saltwater and even freshwater aquariums. These are not to be confused with under
gravel filters.SUMMARY OF LEVELS;In healthy aquarium ammonia and nitrites should
be at 0 ppm In a healthy freshwater aquarium Nitrates should be 15-50 ppm (below
15 ppm is not healthy for planted freshwater aquariums). In a healthy Saltwater
fish aquarium nitrates should be below 40 ppm. In a healthy Marine Reef aquarium
nitrates should be below 20 ppm (or even less).AQUARIUM CYCLING:These major
additional benefits result from the constant removal of Nitrate by bacterial
action in the plenum. My preferred cycling method (it was not in one of the
links) is to transfer filter media (sponges work best) from an established
aquarium along with some gravel, then introduce the fish SLOWLY starting in a
day or two. The method of adding ?aged? media is much faster (you still have to
take it slow), and provides all the necessary bacteria, the only negative is
adding disease pathogens to your aquarium, but I have rarely encountered this
problem. To prevent this transfer of disease pathogens and parasites, only use a
media source where no new fish have been added in 30 days, ALL water parameters
are good, and if possible has UV Sterilization (although not necessary). Also
keep in mind that many pathogens such as pseudomonas are usually present in a
healthy aquarium, but when fish are stressed, the fish are in poor health due to
poor feeding and lack of proper minerals, and/or water conditions are less than
desirable- these pathogens will be opportunistic and cause a disease in the
fish. We used this method for our Aquarium Maintenance route for years and never
lost a fish to Ammonia or nitrite poisoning, and disease transfer was
minimal.There are many products for cycling available too, but most in my
opinion do not work well (although properly cared for BioSpira is
effective).Another method is fishless cycling where un-scented pure ammonia is
poured into the aquarium (3-5 drops per gallon pure ammonia) so as to bring your
ammonia level to 4-5 ppm. Then it takes about 3-8 weeks for the aquarium to
cycle. Although this method is growing in popularity, I do not recommend it, not
because it does not work (it does), but because human nature is to want to add
fish sooner than the 3-8 weeks it takes for this method.Another method is the
gradual addition of fish food to an otherwise empty aquarium (no fish). This can
be a very effective means of cycling that is preferred by many experienced
aquarists. The method of adding ?aged? media is much faster (you still have to
take it slow), and provides all the necessary bacteria, the only negative is
adding disease pathogens to your aquarium, but I have rarely encountered this
problem.For a picture expalining the nitrogen cycle, please visit this URL:
Aquarium Nitrogen Cycle By Carl StrohmeyerAquarium Information American Aquarium
Products - The American coffee craze enters the new millenium. As I sip my
extra hot, nonfat vanilla latte I realize that my Chico State University days
are now just a faded, distant memory. Seven years have passed and the late
night cramming sessions while sipping tepid mochas served by vapid-looking
grungesters in Caf Maxx are just a hazy blur. I am now entering the New Java
Millenium. Recently, I thought about my most favorite research paper I wrote
in college. I was an American Studies minor and for an American I wrote about
Americas Coffee Culture. The project still burns brightly in my caffeinated
brain. Whats happened to Americas coffee culture? I am slowly realizing that
America has entered the Millenium and the java culture has boomed without me.
As we move into the 00s, Americas coffee culture literally spills into our every
day lives. The most recent jab at the modern coffee scene was depicted in the
campy, independent mock-u-mentary film, Best in Show. A whiny, yuppie couple
details how they met at Starbucks. Actually, he frequented one Starbucks while
she clacked away on her laptop at the Starbucks across the street. The
hilarious dialogue of their soy latte whipped frappes and extra hot double capps
made me laugh. Best in Shows satirical diatribe on Starbucks accurately depicts
coffee culture influence amongst Millenium suburbanites. Not only am I a
certifiable java junkie but I make it a point of observing other java addicts in
their natural habitats: lurking in coffeehouses and other eateries where a cup
of joe is the beverage of choice. As a teenager, I thought coffee was for older
people. As I stare vacantly ahead in line at Starbucks, I watch in amazement as
Britney Spears-esque girls order double espressos and then shoot them down
without batting an eye. Didnt their parents warn them that coffee stunts their
growth? I guess not. I didnt know teenagers were drinking coffee these days.
Although, there are still many tried and true coffee drinkers that stick with
their Maxwell House and instant Folgers and steer clear of froofy drinks, as my
father affectionately coins espresso drinks. My dad would be one of the
lingering breeds of black coffee drinkers. Although, my dad has caught up with
the java elite and he now frequents Starbucks on a regular basis. Even my
father has given into the Milleniums coffee culture. The other coffee
phenomenon that is catching on quickly is the cyber caf. You can grab a latte
and then catch up with your email. The conception of the cyber caf depicts where
our fast-paced, techno-culture is taking us: where two addictions (coffee and
the Internet) are coupled together in the most sinful of relationships. The
marketing concept is brilliant and appeals to those who need to satiate both
addictions in one quick fix. The other fascinating trend that reflects our
current culture is the obsession with healthy coffee alternatives. My mother is
a prime example. She is very health-conscious and has to watch her dairy
intake. Her favorite concoction is a decaffeinated soy latte. Soy? When I was
in college, soy wasnt even invented (well, it was but I think it was used to
feed livestock). With the influx of Americas healthy habits, coffee
establishments offer milk substitutes such as soymilk. Also organic,
chemical-free coffee beans are sold and served in coffeehouses which again
reflects Americas health consciousness. As my caffeine buzz fades and I log on
to my computer, I reminisce and try to conjure up the good old days of Americas
coffee cultureah, when a mocha was a mocha and Starbucks was a new concept. It
looks like I need to wake up, grab my soy latte, and join Americas coffee
culture at the cyber cafes. Welcome to the New Java Millenium. About the
AuthorTherese Pope is a non-profiteer fundraiser by day and a freelance writer
and poet by night. Her works have been published in various e-zines and
literary anthologies. She is a yoga fiend with a penchant for writing with
latte in hand. She resides in Sacramento, Calif.
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