* FO (Fish-Only) System: This is an aquarium that contains fish, and no live corals or
rocks. Instead decorative items such as non-living rocks, shells, and dried or synthetic corals are placed in the tank with
fish. Often some "compatible" tank cleaning crustaceans such as algae and detritus eating true crabs, hermit crabs, and snails
are included.
* FOWLR (Fish-Only With Live Rock) System: This type of aquarium usually consists of a combination of
fish with some crustacean and invertebrate tank-mates that are compatible with one another as well as the life that grows
on live rock, such as sessile invertebrates that may be present. No live corals are included. This setup adds the benefit
of natural live rock filtration.
* Reef Tank System: Incorporates the use of live rock, corals, invertebrates, some
reef compatible janitorial type motile invertebrates and crustaceans, and usually only reef compatible fish, or even no fish
at all.
Glass or Acylic?
A glass aquarium is basically a glass "box" formed using individual pieces of glass held
together with heavy plastic top and bottom frames. Silicone is used to seal between the glass pieces and the frame. The silicone
seal not only prevents leaks, but also cushions one piece of glass against the other, which aids in preventing pressure cracks.
Glass aquariums are warranted against pressure cracks and leaks.
Glass aquariums are very easy to clean, they don't
scratch as easily as acrylic, and they are generally less expensive than acrylic. They're made in a wide variety of shapes
and sizes - from 5 gallon up to 240 gallons and larger. Traditionally, glass aquariums came only in square or rectangles.
However, new technologies now make bending of glass possible and glass aquariums now come in many new shapes and sizes.
Acrylic
aquariums are more expensive than glass aquariums, but there are a number of advantages that account for the difference in
price. Also, remember that in large aquariums the cost differences between glass and acrylic aquariums are generally much
less.
Acrylic aquariums are usually constructed by using a solvent to weld the seams. This technique assures that
an acrylic aquarium will rarely develop a leak. After the aquarium is assembled, the solvent evaporates and the seams become
stronger than the acrylic itself. These solvents pose absolutely no danger to the fish within the aquarium. Silicone seams
can discolor with age; solvent used in acrylic aquariums does not yellow with age. Acrylic aquariums can also be heat formed
for a seamless design.
Acrylic is 17 times stronger than glass and will flex instead of shatter. This makes it virtually
childproof. Because the seams are stronger and the aquarium is more flexible, you can count on having an acrylic aquarium
longer. It's also more clear than glass, and is a better insulator than glass, which means it takes less energy to heat the
aquarium. Acrylic weighs half as much as glass, and the bent corners and fewer seams on an acrylic aquarium adds a sleek design
to the tank.
Another advantage to acrylic is the endless shape possibilities. You name it; cylinders, arches, just
about any shape imaginable can be reproduced in acrylic.
One drawback of acrylic aquariums is the tendency for scratches.
However, scratches can be removed or lightened from acrylic whereas it is impossible to remove a scratch from glass. Because
acrylic aquariums can scratch easily, only those scrubbers that indicate "can be used on acrylic" should be used. Never use
an ammonia product when cleaning the outside of an acrylic aquarium because ammonia will crystallize acrylic. Use only a vinegar
and water solution for cleaning the outside of an acrylic aquarium.
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