Nitrification, Denitrification, And Cycling Methods'
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 goal of achieving optimal fatty acid nutrition must be
approached by altering the fatty acid composition of the day-to-day meal
pattern. If the diet is high in saturated fats, more of the positions on the
glycerol backbones will be taken up by saturated fats. If the diet is high in
omega-6 fats or hydrogenated fats, more of the positions will be taken up by
those fatty acids. If one can begin to increase the consumption of known
health-enhancing fats, then the triglyceride and phospholipid pool will convert.
This will in turn exert beneficial effects on membrane physiology and provide
precursors for eicosanoids that exert health-enhancing rather than
health-robbing effects.OMEGA- 6 RECOMMENDATIONS Various recommendations by
research organizations have indicated certain minimum dietary levels for
essential fatty acids. For example, for humans, the World Health Organization
suggests that 3% of calories should consist of essential fatty acids for an
adult and 5% for children. The essential fatty acids they specify are linoleic
and linolenic acids. Specific recommendations made by United States governmental
agencies suggest that linoleic acid should comprise approximately 12% of
calories. Some argue this should be increased to as much as 10% for optimal or
therapeutic effects.But this minimum recommendation for linoleic acid is not
only met by modem food sources, it is usually exceeded to the extreme. For
example, the average American would need only to consume about 45 milligrams of
linoleic acid per kilogram of body weight per day, but they are consuming over
300. The same disparity exists for animals on modern processed foods.High
dietary omega six fatty acids are common but essential fatty acid deficiencies
are paradoxically also common. This is due to a variety of factors. The
increasing use of warm weather seeds, which now predominate in modern
agriculture, provides the excess supply. The "fat tooth? that modern cultures
have is satisfied by large portions of omega-6 oils in processed foods. The
discovery of cholesterol in atherosclerotic plaques, leading to the conclusion
that cholesterol should be excluded from the diet, also led to increased
consumption of vegetable (omega-6) fats. Although exceeding the minimums
quantitatively is apparently easy, the quality of fatty acids is threatened by
the very nature of processing itself, which can readily degrade essential fatty
acids into nonutilizable or even toxic forms. The primary goal should therefore
be to decrease omega-6 fatty acids in quantity and increase their quality while
at the same time increasing the omega-3 to omega-6 ratio in the diet.OMEGA-3
RECOMMENDATIONS Sources of omega-3 oils include fish, wild meat and animal
products from animals on high omega-3 diets, as well as certain seeds such as
flaxseed, chia, rape, cold-weather nuts and soybeans. Other sources include
mosses, ferns, alfalfa, the bark of certain trees, and phytoplankton which have
the metabolic machinery (desaturase and elongase enzymes) within chloroplasts to
convert omega-6's to omega-3's. But normally these sources are not consumed to
any degree by non-wild higher mammals. Wild animals have not only less fat, but
a higher omega-3 to omega-6 fatty acid ratio in tissues.1 (Fig. 30)The
recommendation for linolenic acid (plant source omega-3) to prevent deficiency
is .54% of calories.2 Others suggest a level ranging from 0.8% to 1.2%.3 More
important than absolute amounts of linolenic acid would be the ratio
corresponding to linoleic acid and perhaps other fatty acids. Clinical
effectiveness, as can be predicted from a synergonic view, has been related to
balance rather than dose.4,5 The ideal ratio can be deduced from the respective
levels of these oils in many common natural foods and also the ratio which
exists in mother's milk. This ratio seems to be approximately 5: 1, with
linoleic acid comprising the greater proportion. (Fig. 33)Unfortunately some
American mothers have ratios exceeding 30: 1.6,7 A minimum of 11/2 grams per day
of linolenic acid for humans has been suggested for maintenance and over 100
grams per day have been utilized in therapy.8Omega-3 fish oils consumed
specifically to treat or prevent cardiovascular disease should make up 2% of
daily calorie consumption according to some researchers. This would amount to
approximately five grams per day. As much as 10-20 grams or even more per day
has also been suggested.9 Some, however, report that relatively small doses can
create a beneficial effect.10 Others report an unfavorable shift in LDL-C and
LDL-apoprotein B concentrations in low doses compared to the higher ones.11 Such
confusion and contradiction abounds when attempting to design diet based on
doses of isolated nutrients... benefits are possible but so are dangers.OMEGA-3
DANGERS There are a variety of dangers associated with the consumption of high
levels of fish oils. Increased bleeding time may create risks for cerebral
vascular accident and epistaxis (nose bleed).12,13 Fish oils have recently been
shown to increase LDL levels and thus potentially predispose to cardiovascular
disease rather than prevent it.14 Depletion of body reserves of vitamin E used
to stabilize these highly reactive oil molecules (potential steatitis, yellow
fat disease, may result but is prevented with vitamin E supplementation -- the
dose required being up to six times normal levels), free radical and peroxide
generation from the spontaneous degradation of these oils, and over-consumption
of heavy metals (mercury etc.) and chlorinated hydrocarbons or toxins which may
concentrate in fish oils.15,16Since fish are higher on the food chain than plant
sources of omega-3, the risk of toxin concentration is of course greater.
Although linolenic acid is believed to be approximately 1/5 as effective in some
therapies as EPA derived directly from fish oil (since it must go through
enzymatic steps to convert to EPA), many would argue that this is the preferred
source of omega-3 fatty acids since this dietary source could simply permit the
body to regulate its own requirement for EPA. 17,18OMEGA-9 RECOMMENDATIONS
Omega-9 oils derived from olive and other sources are not considered an
essential dietary fatty acid. However, an impressive body of evidence indicates
their health and nutritional benefits. Doses of as high as 10% of dietary fats,
or 1 ounce of olive oil per day is one recommendation based upon research on the
effect of omega-9 fatty acids on various health parameters.19-21PHOSPHOLIPID
RECOMMENDATIONS Phospholipids are a predominant part of all cellular and
organelle membranes and thus are an extremely important biochemical component.
They are particularly rich in brain tissue, sphingosines, and in sphingomyelin.
The choline fraction of phosphotidl choline is a component of the neuronal
transmitter acetylcholine. There is no dietary requirement for phospholipids
since the body is capable of manufacturing them. However, there is a
considerable body of medical literature indicating the beneficial effects of
supplementing lecithin, phosphotidl choline, to the diet. A dosage of choline
ranging from three to twelve grams per day has been used for such conditions as
tardive dyskinesia, pre-senile dementia, Alzheimer's disease, manic depression,
diabetic peripheral neuropathy, and a wide range of other neurological and
locomotor as well as autonomic dysfunctions in humans and animals.
22-28SATURATED FAT RECOMMENDATIONS There is no recognized dietary requirement
for saturated fat. However, it is and always has been a part of dietary makeup.
Although saturated fats have received considerable "bad press," recent studies
have shown stearic acid (18:0) to actually decrease blood cholesterol
levels.29,30 (A method of determining the level of saturation of fats is to
place oil in the refrigerator. Saturated fats will become hard, a mixture of
saturates and unsaturates will become cloudy, whereas a pure unsaturate will
remain liquid.)Saturated fat intake, as with cholesterol intake, may be more of
a concern because of its relationship to particular dietary patterns. The
modern, highly processed, high fat diets invariably have high saturated fats and
high cholesterol levels and are positively associated with various degenerative
diseases. Evidence supports the relationship between low saturated fats in the
diet and decreased serum cholesterol levels. Additionally, the ratio of
saturated fats to unsaturated fats is an important criterion for measuring
risks. Maintaining an unsaturated fat to saturated fat ratio of 3 to 1 or
greater and keeping total fats to less than 30% of dietary calories are widely
accepted as guidelines for decreasing cardiovascular risk.31GUIDELINES The above
discussion is not meant as a recommendation to carefully measure oils in the
diet on a gram scale or to seek a potpourri of capsules. The inference from the
data is the value of natural whole, fresh foods. If these are carefully
selected, the quantities and ratios have already been taken care of by the best
chemist of all, nature.Certain practical rules of thumb will help alter the
essential fatty acid content of the diet to enhance health: 1) Consume
increasing amounts of fresh, whole organically grown fruits and vegetables,
seeds and nuts; 2) If cooking is done, cook without oils or cook with olive oil,
high omega-9 commercial products, lard or butter (since these saturated fats are
the most heat stable against oxidation); 3) Minimize cooking temperatures and
try to eliminate cooking as much as possible; 4) Incorporate natural raw foods
into the diet known to contain high levels of omega-3 and -9 oils; 5) Increase
the ratio of omega-3 fatty acids to omega-6's; 6) If wishing to derive omega-3
fatty acids from fish, poach or broil fish known to contain high levels of
omega-3 fatty acids (Fig. 33); 7) If fatty acid oil supplements are used, they
should contain balances of the oils as described above and be properly
stabilized with antioxidants (natural, if possible), packaged in light
impervious safe containers (some plastic components will leach into oils) and
nitrogen flushed. Supplemental vitamin E (200-400 I.U. per day) should also be
consumed when any isolated fats and oils are added to the diet.COMMERCIAL
RESPONSIBILITIES AND OPPORTUNITIES From a commercial standpoint, this new
knowledge creates excellent opportunities to improve food nutritional value as
Dr. Kinsella of Cornell's Institute of Food Science points out:"The food
industry (both producers and processors) should explore methods for adjusting
the amounts and ratios of PUFA's in food products. Successfully increasing the
w-3 PUFA content of foods will require innovative approaches for controlling
autooxidation and off-flavor development in such foods. The discovery of
multiple and potent effects of eicosanoids and the apparent beneficial effects
of w-3 PUFA's has invigorated biochemical lipid research and has presented
opportunities for making significant progress in the amelioration of
atherosclerosis, perturbed immune functions. Cancer, arthritis, and thrombosis,
the major causes of death and debility in the U.S. Knowledge of the links
between dietary fatty acids and the incidence and severity of these degenerative
diseases will provide further rationale for modifying the lipid prof1les of
existing food products and developing new food products to improve nutrition and
the quality of life of this and future generations."32Whether industry will
responsibly act on this information remains to be seen. Since considerable
pressure exists within the modern corporate environment to prioritize the bottom
line, rather than simply "do good," change will not likely occur until consumer
demand creates a commerciable opportunity. An informed consumer using the power
of the dollar will therefore likely be the ultimate reason our food supply
changes for the better.References available within book text, click the
following link to view this article on wysong.net:
http://www.wysong.net/articles/lipid/11_article_lipid_chapter_eleven_dietary_approach.shtmlFor
further reading, or for more information about, Dr Wysong and the Wysong
Corporation please visit www.wysong.net or write to wysong@wysong.net. For
resources on healthier foods for people including snacks, and breakfast cereals
please visit www.cerealwysong.com.Dr. Wysong: A former veterinary clinician and
surgeon, college instructor in human anatomy, physiology and the origin of life,
inventor of numerous medical, surgical, nutritional, athletic and fitness
products and devices, research director for the present company by his name and
founder of the philanthropic Wysong Institute. http://www.wysong.net Also check
out http://www.cerealwysong.com
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