FREE ESSAY ON MAINTAINING MARINE REEF AQUARIUM

MAINTAINING MARINE REEF AQUARIUM

Important Aspects in Maintaining a Marine Reef Aquarium
There is something fascinating and relaxing in having an aquarium in a home. Like a
fireplace's warm glow and bright colors, the colors that are emitted from an aquarium can
be just as warm and even more colorful. From the slow and graceful movement of the fish
to the frantic feeding frenzy, an aquarium is different each time it is viewed. Although
a freshwater tank can be full or color, it does not come close to the fiery colors that
are present in a marine aquarium. Unfortunately, all the color and life that a marine
aquarium holds is much more fragile and not as easy to keep as a freshwater tank.
Therefore, the marine aquarium requires a plethora of devices working together and at
optimum levels to maintain a successful tank. Items like protein skimmers, ultraviolet
filters, sump filters, reverse osmosis units, and even wave-makers are just a few of the
devices that are required to properly maintain a marine aquarium. With the exception to a
properly constructed tank, nothing is as important to the marine aquarium as the water
within the tank and the lighting given its inhabitants. 
Since water is the medium that the aquarium inhabitants must live in, it is the most
vital component in any tank. The quality of the water used will directly effect how
successful the aquarium is. The chemical balance of the water must be watched closely. If
the salt content varies too much, or harmful chemicals build up, the water will kill the
inhabitants of the tank. 
Since fresh pure sea water is not readily accessible, the easiest water source for the
majority of hobbyists is the faucet. However, the tap water that comes from the local
water treatment plants may be safe for human consumption but is most likely toxic to
marine life. Water treatment plants remove most of the harmful chemicals, but the water
delivered is anything but pure. Often this tap water contains high levels of phosphates
and nitrates that can be harmful to aquarium inhabitants. Also, copper may leach from
pipes, and it is deadly to marine invertebrates (Goldstein 8). This leaves very few
options for water to the hobbyist. One of the last, and probably the best option for
obtaining a pure water source is by using reverse osmosis water.
Reverse osmosis is a process of filtering out pollutants from water to create a purer
form. Mr. Dakin who has written several books on maintaining a reef aquarium describes
osmosis in his book as "a natural process by which selective molecules in an aqueous
solution can be pass through a semi-permeable membrane, while the movement of other
molecules due to size, shape or other reasons is restricted" (20). Once water has been
allowed to flow through this membrane, purer water can be collected from the output of
the filter. Once enough of this water is collected, the hobbyist can fill the aquarium
and begin to plan on his or her next step, the salt content.
"Although ocean water tastes like water with table salt (sodium chloride) dissolved in
it, it is a lot more complex than that" (Friese 33). Pure sea water contains a vast
amount of dissolved chemicals. It contains everything from sodium chloride to trace
amounts of silver and gold. Although the inhabitants of a marine reef aquarium are not
going to be effected if the water does not contain gold, they will not live long if all
that is added is table salt (Friese 33). Marine salt mixes contain a similar collection
of elements that are found in natural seawater. 
There are many different brands of aquarium salt available to the hobbyist, and each one
has its own following of people that will swear by its use. Any brand available will work
since it is very unlikely the inhabitants will be able to tell the difference. However,
what is more important than the brand of sea salt is the amount that is added to the
water.
Water in the open ocean contains around 34 parts of dissolved inorganic materials for
every 1000 parts of water (Friese 34). This is where the marine reef inhabitants live and
thrive. For the hobbyists to have their inhabitants live and thrive, they must strive to
keep the water in their tank as close to this as possible. Instead of using a microscope
and attempting to count particles, the most accurate way to do this is by using a
hydrometer. A hydrometer measures the specific gravity of the water, or how dense the
water is. The higher the concentration of dissolved elements in the water, more commonly
referred to as salinity, the denser the water becomes. 
Salinity will also change with a change in temperature, and most hydrometers are
calibrated at a specific temperature. Since this calibrated temperature will most likely
be different than the temperature of the water in the tank the hobbyist must read the
hydrometer with care. The best way to get an accurate reading is to chill a sample of the
aquarium water until it reaches the calibrated temperature of the hydrometer (Friese 35).
As awkward as this can be, it will give the hobbyist the most precise reading possible
without obtaining $400 plus testing equipment. 
Now that the aquarium has been filled with water and a correct amount of salt mix has
been added, it is very tempting to add fish. This would be a costly mistake. The aquarium
at this point is sterile, and the filtration systems that are connected to the aquarium
are only removing debris from the water. Whether the aquarium has one filter or 100
filters connected, all they are doing is cleaning the water. Without the proper bacteria
introduced in the tank the inhabitants would quickly die from their own byproducts
(Shimek 63). 
The easiest way for the hobbyist to introduce bacteria is by adding live rock or live
sand. Live rock and live sand are nothing more than rocks and sand from an established
aquarium. The bacteria that live in these materials will quickly multiply and spread
throughout the new aquarium. This bacteria makes up a biological filter that removes
waste byproducts in what is known as the nitrogen cycle. The nitrogen cycle is basically
a three-step conversion of harmful products in the tank to products that are somewhat
beneficial.
The first step in the nitrogen cycle is to convert ammonia in the tank into nitrites.
Just as trees and plants ingest carbon dioxide to produce oxygen, animals that consume
protein for food produce ammonia as waste products. Ammonia in a marine reef aquarium is
extremely toxic to the inhabitants if they reach levels of .0002 grams per liter of water
(Shimek 63). Levels even lower than that will cause stress to the inhabitants, which
makes them susceptible to diseases. Some of the bacteria that live within the filter
media and throughout the aquarium digest ammonia as food and expel nitrites (Madison 41).

Nitrites are not as toxic as ammonia, however they are still toxic to the inhabitants. So
the second step in the nitrogen cycle is to get rid of the nitrites. Other bacteria
within the aquarium remove nitrites in the same way that the ammonia is removed (Madison
42). This second form of bacteria will consume the nitrites as food, and expel nitrates
back into the tank.
The last step of the nitrogen cycle is to rid the aquarium of nitrates. Although fish and
invertebrates can stand a higher level of this chemical, it is something the hobbyist
must watch closely. There are bacteria that will consume the nitrates, but at a much
slower rate than ammonia or nitrites are consumed (Madison 42). This allows some forms of
algae to feed on the remaining nitrates. Although some algae growth in a marine aquarium
is beneficial, an algae bloom can occur if nitrate levels grow too high. The best way to
control nitrates within a marine aquarium is by doing partial water changes on a regular
basis (Paletta 3). 
Replacing 10% to 20% of the water every month is an ideal way to keep nitrate levels low
(Paletta 3). This also will eliminate other harmful chemicals from building up, such as
phosphates. Phosphates within the tank can quickly cause algae to grow over everything
within the tank. The hobbyist can had certain chemicals to rid the aquarium of the
harmful chemicals, but experience has shown that the added chemicals can cause harm for
certain tank inhabitants (Walker).
Although these are the main chemicals the hobbyist must watch out for to keep from
killing the tank inhabitants, there is one other chemical that requires a constant watch.
To promote healthy growth, calcium levels in the water must also be watched. Calcium is
primarily a self-replenishing chemical; the rocks and sand in the aquarium contain
calcium, and as this material slowly dissolves the level of calcium will be maintained.
However, in aquariums containing high amounts of live corals, the calcium may be depleted
faster than it can be replenished (Goldstein 21). In these cases, the hobbyist must add
calcium supplements to his or her aquarium. 
"Apart from good water conditions, the single most important factor in the success of any
aquarium containing photosynthetic organisms is the quantity and quality of the light
provided" (Tullock 105). There are a variety of options for the hobbyist to consider when
it comes to lighting his or her tank. At first this might appear to be an easy subject.
Put the aquarium under a window so it will receive natural sunlight, or place a few light
bulbs from a hardware store over the top of the tank. Both methods would be a drastic
mistake. First, direct sunlight would cause a tremendous growth of algae, much like algae
will grow in a pool or pond. Secondly, normal light bulbs put out a frequency of light
that is suited for human eyes but lack most of the light spectrum that is required for
coral growth. A tank lit in this manner would quickly kill off most of the corals and
invertebrates that are popular in the marine aquarium (Larson).
What the hobbyist needs for his or her aquarium is specialized lighting. Lights that
provide the correct spectrum and most closely resemble direct sunlight are best for most
aquarium inhabitants. How large the tank is and what inhabitants are residing in the tank
will determine how much lighting is required. 
The ideal setup would provide an equal amount of light, and a spectrum of light that
resembles direct sunlight (Gamble). Since this would be extremely expensive and difficult
to achieve, an easier way to determine the amount of light needed is to have four to
eight watts of light for every gallon of water in the tank (Larson). For example, a 75
gallon aquarium should have from 300 to 750 watts of light. There are four main lighting
options that will fill these needs. All of the options include some form of florescent
lamps, and can be mixed to provide optimum lighting conditions to any aquarium.
The first option is to stick with the lighting that comes with a newly purchased
aquarium. These lights, referred to as Normal Output (NO) bulbs, are very low power, only
providing 15 to 20 watts of light per bulb. These bulbs are also the cheapest option of
providing light to the aquarium (Reefkeeper's FAQ). Because of the low output of these
bulbs, they are a poor option for lighting a marine aquarium.
The next option for the hobbyist is High Output (HO) lights. This type of lighting is
identical to NO lights except they provide a higher output of light, normally 50 to 75
watts per lamp (Reefkeeper's FAQ). However, because these lamps still provide a low
output of light they are best suited as supplemental lighting to the aquarium.
The most common lighting for a marine aquarium is Very High Output (VHO) lamps. These
lamps provide from 75 to 110 watts of light per bulb, and when used in quantity they can
easily provide enough light to satisfy the needs of any inhabitants (Reefkeeper's FAQ).
Yet to provide enough light for an average sized aquarium, at least four of these bulbs
would be needed. Therefore, this form of lighting can be extremely expensive and create
an abundance of heat that needs to be dissipated. 
The last option, and probably the best option for lighting are Metal Halide (MH) lights.
This form of lighting is also florescent, but it is shaped more like a standard light
bulb. Although expensive, these bulbs can provide a much higher output, from 150 to 400
watts per lamp (Reefkeeper's FAQ). Even though these lamps are expensive, the cost per
watt of light is actually less; since only one or two bulbs are needed for an average
size aquarium.
Once the aquarium is lit properly and the hobbyist has the water quality he or she needs,
fish and other animals can be added. Yet, the hobbyist is not done with either water
checks or the lighting. Both are something that will require a constant watch.
Each time a new fish or invertebrate is added to or removed from the tank the chemical
balance of the water is upset. The bacteria within the tank will then have to readjust
either by reproducing more or dieing off. In either case, the ammonia levels will
temporarily rise until the chemical balance of the water settles back down. This requires
the hobbyist to consistently monitor the water. If he or she does not, the quality of the
water may quickly become uninhabitable.
Lighting also requires constant watch. As the bulbs age, the output power and light
spectrum will change. Most florescent bulbs will last around 18 to 24 months
(Reefkeeper's FAQ). To keep good lighting conditions within the tank, good rule of thumb
is to replace the bulbs within the tank every year. 
With properly maintained water and lighting, the marine aquarium can become a showpiece
in any home. What appears to be a lot of work monitoring water conditions and lighting
quickly becomes only a minor chore as the aquarium begins to regulate itself. Considering
the amount of work and money a fireplace requires, the aquarium is a much easier and
cheaper centerpiece that can be added to any room. It becomes a landscaping of art that
even the best painters have difficulty capturing, and can be enjoyed by everyone. 
Bibliography
Dakin, Nick, The Marine Aquarium Problem Solver. Blaksburg, VA: Tetra Press, 1998.
Friese, U. Erich. Keeping a Reef Aquarium. Neptune, NJ: YearBOOKS Inc, 1996.
Gamble, Sam. Light Energy 5 October 1999.
Goldstein, Robert J. Marine Reef Aquarium Handbook. New York: Barron's Educational
Series, Inc, 1997.
Larson, Scott. Personal Interview. 10 September 1999.
Madison, Pieter. "You Can Succeed with Marines." Tropical Fish Hobbyist. August 1999:
38-46.
Paletta, Mike. "Water Changes." SeaScope, Fall 1997, 3.
Reefkeeper's FAQ. 18 September 1999. 
Shimek, Ronald L. "So, You Want to Join the Marines." Aquarium USA, 1999: 61-75.
Tullock, John H. Natural Reef Aquariums. Shelborne, VT: Microcosm Ltd, 1997.
Walker, Matt. Personal Interview. 20 October 1999