Plants grow rapidly in response to dissolved
nutrients that are excreted directly by
the fish or generated from the microbial
breakdown (mineralization) of fish wastes.
In closed recirculation systems with very
little daily water exchanges (less than 5%),
dissolved nutrients accumulate and approach
concentrations that are found in hydroponic
nutrient solutions. Dissolved nitrogen, in
particular, can occur at very high levels in
recirculating systems. Fish excrete waste
nitrogen directly into the water through
their gills in the form of ammonia. Bacteria
convert ammonia to nitrite and then to
nitrate. Ammonia and nitrite are toxic to
fish, but nitrate is relatively harmless and is
the preferred form of nitrogen for growth
of higher plants, such as fruiting vegetables.
It is the symbiotic relationship between fish
and plants that makes the consideration of
an aquaponics system a reasonable system
design criteria.
As existing hydroponic and aquaculture
farming techniques from the basis for all
aquaponics systems, the size, complexity, and
types of foods grown in an aquaponics system
can vary as much as any system found in
either distinct farming discipline.
AgriKultuur |AgriCulture
What is a Microbe?
A microbe, or “microscopic organism,” is a
living thing that is too small to be seen with
the naked eye. We need to use a microscope
to see them.
The term is very general. It is used to describe
many different types of life forms, with
dramatically different sizes and characteristics:
• Bacteria
• Archaea
• Fungi
• Protists
• Viruses
• Microscopic Animals
Under natural conditions, a microorganism
rarely exist in isolation. Even when a single
microbial cell is successfully isolated in
the laboratory, the individual normally will
multiply and form a group (a clone) of similar
individuals called a population. Typically, in a
natural environment, numerous populations
of different character coexist. The microbial
populations that live together at a particular
location, called a habitat, interact with each
other to form a microbial community. The
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