The Nitrogen Cycle & Nitrifying Bacteria
Ever wonder why your shrimps are dying within a week of introducing to a newly setup tank?
Step# 1 - To begin, you will need to understand and have sufficient knowledge of The Nitrogen Cycle. It is the process in which nitrifying (aka beneficial) bacteria breaks down nitrogen based compounds gradually from Ammonia (NH3) to Nitrite (NO2) and finally to Nitrate (NO3).
Ammonia is resulted from large amount of waste such as excrement from shrimps, decaying plant, leftover food and all other organic matter in the aquarium. Since Ammonia and Nitrite are extremely toxic to Crystal Red shrimp, it is necessary to remove them from the tank through this process of breaking down to Nitrate which will be absorbed by plants.
In a newly setup (uncycled) aquarium, nitrifying bacteria are already presence in the
water, gravel and filter system. It is critical that these
beneficial bacteria
thrive to a large population in order to breakdown the waste that will
eventually be produced within the aquarium ecosystem. Even with a cycled tank,
as the population of the shrimp increases, more and more Ammonia will be
produced. The aquarium requires time to build up adequate nitrifying
bacteria to counter the waste produced. This direct relationship
between Ammonia and the nitrifying bacteria is commonly known as
Bio Load.
THE NITROGEN CYCLE:
To start off the Cycle, there must be Ammonia presence in your
new aquarium. Since most shrimp tank setup will probably
use processed soil as the gravel, this should not
be a problem. Nitrifying bacteria known as Nitrosomonas,
takes about 7 to 10 days to build up sufficient amount in order to convert
Ammonia to Nitrite.
During this period, Nitrite, an equally toxic substance is also presence in the water. This requires another nitrifying bacteria known as Nitrobacter to convert it to Nitrate. Nitrobacter can only thrive well in the absence of Ammonia, it will take another 14 to 21 days for the Nitrobacter to build up and convert Nitrite to Nitrate.
Based on the above, it takes at least
3 to 4 weeks to complete the Nitrogen cycle. In some occasions, it
takes up to 6 weeks. During the initial stage, it is
recommended to check with Ammonia and Nitrite test kit every 3-4
days. Once the aquarium tank is fully cycled, a monthly periodic
check is recommended or whenever the tank has problem.
Although Nitrate is not really a toxic to the shrimps, it is best to
keep below 3ppm for your aquarium (Crystal Red Shrimp is
sensitive to high nitrate). Too much Nitrate can also cause algae blooms.
Nitrate can be reduced by a weekly water change at 10-15%, or consumed
by rapid growing aquatic plants like frogbit or waterpoppy.
Both Nitrosomonas and Nitrobacter are Aerobic bacteria which means
they require oxygen to thrive. They will fix themselves in any
surface location with a good supply of oxygen, low or no lighting and
water current that is not too turbulent. In an enclosed aquarium
tank, the surface area in contact with the water flow that matches
the criteria is either the gravel or the filter system. This is why
pro hobbyists use Under Gravel Filter (UHF), porous filter media to
provide enough space to grow these bacteria.