On the MoreBioFilteraton page, we have only
briefly mentioned the different technologies
used in maintaining the biological filteration
aquariums. Here we would like to include
the details of the different technologies
that we did not covered on the that page.
We mentioned that the denitrification filter
is responsible for the dissimilation process
in the denitrification cycle. The dissimilation
process is very important because if it fails,
we will have nitrate and nitrite left in
the tank. So a good denitrification filter
is a-must in maintaining your tank. Below
is another picture of the denitrification
filter:
Here is a re-take of the same denitrification
filter together with the Deni-Balls from
Aqua Media. The denitrification tower has
a circulation pump on the top to circulate
the water inside. But remember, we do not
want a strong circulation. Unlike a biological
filter, the bacteria living in the tower
is anaerobic in nature. The black balls inside
the tower are where the bacteria live. Each
ball can be thought of having many slices
of plastic glued together. This is to allow
as much the interior of the ball to be taken
away as possible. This, in turn, allows more
water to flow through and so there is a larger
surface area for the bacteria to make contact
with the ammonia and ammonium.
The Deni-Balls besides the tower actually
contain bacteria needed to set up the dissimilation
process. In order for the denitrification
filter to work, you must put in a certain
amount of Deni-Balls to kick off or to maintain
the cycle. The number of Deni-Balls that
you must use will depend on a few factors:
1) Are you setting up a new tank?
2) Has your filter been running? Generally
speaking, an used filter already has a certain
amount of bacteria living inside. The cycle
can then be accomplished earlier than using
a brand new filter.
3) How big is your tank?
4) How much bio-load is already present in
the tank?
If you are uncertain about how many Deni-balls
you should use and how often the replacement
you should do, please check with your local
pet shop.
Always remember that the effluent of this
filter is extremely low in oxygen, so never
connect the outlet of this filter directly
to the tank. Connect the outlet back to the
sump or to your other filteration unit at
all time.
Towards the end of the MoreBioFilteration
page, we have talked about the basic principle
of a protein skimmer. Here we would like
to continue our discussion with a better
protein skimmer.
The turboflotor unit is manufacturered in
Germany and is capable of handling 125 to
250 Gallons. This unit, unlike the simple
Lee's product shown before, has an external
motor (the bottom left) to drive the water
(and air) into the skimmer.
If fully assembled, the plastic pipe is to
be connected between the motor and the grey
nozzle. Water will first enter the motor
and then "processed" before entering
the skimmer through the inlet. The motor
has another inlet for an air pump to be connected.
Inside the motor, there is a needle wheel,
one of the key features of the turboflotor.
The needle wheel is driven by the motor and
is constantly rotating. When the wheel is
rotated, the rotation allows the air entering
to the motor to dissolve into the current.
The significance of the needle wheel is that
rotating the wheel with many fine needles
on it forces the water to go around the needles,
and hence, more water surface is produced.
This increase in water surface makes it very
effective in generating fine air bubbles.
This makes the skimmer work more efficiently
than the simple Lee's skimmer.
With the Lee's product, the fine air bubbles,
which are used to carry the electrically
charged protein molecules to the collection
cup, are generated by an air-stone. You can
easily image that you will need a bunch of
air stones to produce enough air bubbles
once the skimmer exceeds a certain level
of capability. So the simple skimmers that
rely on air stones are only suitable for
small tanks. Compared to the Lee's skimmer,
we say that the needle wheel is one of the
features that the turboflotor 1000 unit is
a better choice. This is because there is
no need to replace any air-stone periodically
(because it has none) and it is much more
effective in generating air-bubbles, the
carrier of the waste.
The turboflotor 1000 unit is a very popular
equipment in our store. These two pictures
are taken from two of our different systems.
The tank on the left is the same one that
we use to demonstrate different lighting
systems - Phase IV, Power Compact - on the
MoreLighting page.
The collection cup has just been cleaned
before this photo was taken. The collection
cup should be cleaned regularly.
Each of the skimmer is placed inside a sump.
Pay attention to the shape of the Foam Raiser
Tube. You see that the Foam Raiser Tube,
the tube inside the collection cup, has a
unique shape. The Foam Rasier Tube has a
shape of an inverted-cone.
This inverted-cone shaped Foam Rasier Tube
is indeed another advantage of this product
as compare to the others. Remember that there are two types of foams
that will be producted when the air bubbles
reach the top: dry and wet foam. We know
that only the wet foam is what we want to
collect. The inverted-cone has such a shape
that it reduces the surface area gradually
as the foam reach the top. The trick is that
the dry foam will stick to the inside surface
of the Foam Raiser Tube, but the wet foam
will reach the top and will be collected
outside the Foam Raiser Tube. Do you see
the foam in the middle of the Foam Raiser
Tube? The top portion of the foam is brownish,
but the bottom portion of foam is white.
The brownish foam is the wet foam and the
white foam is the dry foam. Once the wet
foam reaches the top of the Foam Raiser Tube,
the wet foam will be collected because the
foam is more heavier (because of the water
molecules) than the dry foam. The wet foam
will be collected in the volume outside the
Foam Rasier Tube and inside the collection
cup. So immediately we see that this skimmer
is a lot more efficient than the simple Lee's
product. It handles most of the problem of
sorting the wet foam from the dry foam. For
these two features, the needle wheel and
the inverted-cone shaped Foam Rasier Tube,
we highly recommend this unit to people who
are considering of upgrading their skimmers.
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We mentioned on the MoreBioFilteration page
that it is very important to have a good
current flow in the tank. A good current
flow can distribute oxygen more evenly in
the tank, which reduces the anaerobic zone
in the tank. It can also distribute heat
evenly in the tank so that the temperature
near the water surface is not much different
from the bottom of the tank.
The product that we mentioned before is the
Natural Wave Multi-Cycle Pump Timer manufactured
by Aquarium Systems. Since the publishing
of the MoreBioFilteration page, we have been
receiving a few questions regarding the use
of this particular product. We feel that
it is better to give a concrete example to
explain this interesting point clearly. Let
us have a closer look of the power bar: 
The three rightmost outlets are connected
to the timer. The frequency of the timer
can be adjusted by turning the knob at the
other end. Suppose you have three power heads
inside your tank and you put the first power
head near the water surface, the second one
in the middle of the tank, and the third
one near the bottom of the tank.
From the timing diagram shown on the previous page, you know that
the first power head will be turned on first,
then the second one, and then the third one.
(Let us assume that the first one is connected
to outlet 1, and the second one is connected
to outlet 2, and so on.) Also from the timing
diagram, you see that when the first one
(outlet 1) is on, the other two (outlet 2,
3) are off. So there is a stream of current
flowing near the surface first. Then there
is another stream of current flowing in the
middle portion of the tank, and another stream
flowing at the bottom later on. This is one
way of stimulating the natural wave motion
in your tank. The other way to do this is
to have two powerheads arranged so that their
streams will be opposing to each other. For
example, one is going from the left to the
right and the other is going from the right
to the left. If there is no such power bar
to supply the electricity periodically, the
two streams will always be fighting with
each other. Because the water waves interfere
with each other, the result is usually an
uncontrollable stream in your tank. The overall
stream, however, is not going to be very
useful because how the water waves interfere
with other depends totally on where the power
heads are located, which power head is stronger
than the other, and how the water waves interfere
with the waves bounced off the glasses. There
are too many variables in the tank and since
it is not a physics final exam, it is virtually
fruitless to do it this way. With this kind
of timing devices, however, you can develop
a motion pattern inside your tank very easily.
There is indeed an even better solution to
generate a natural wave motion in the tank.
This involves not only the timer - power
bar, but also better power heads. Below is
the front of the power head. The grey nozzle
is the inlet of the water. To see the back
of the power head, click on the the following
link "better power head".
The better power head is manufactured by
Aquarium Currents Inc. This power head can rotate its outlet by
90 degrees. This can spread the stream more
evenly. The idea of having the rotating power
heads is not new and there are other inexpensive
ones in the market. However, those inexpensive
ones are not quite reliable. Very often the
power head stops rotating after only a few
days of use. To the best of our knowledge,
this product from the Aquarium Currents Inc
is quite reliable and we have not received
any customers complaint about it so far.
We believe that a better solution in simulating
the natural wave motion in your tank is to
combine the timer - power bar together with
a reliable rotating power head. However,
there is no need for you to change all the
power heads to this type of rotating power
heads. If you put a rotating power head in
the right position, it can direct the streams
from the other regular power heads to the
desired direction to eliminate the anaerobic
zone in the tank effectively.
Back to the Table of Content
Recently, we have observed that more and
more customers are interested in learning
about the Redox measusrement. The basic idea
of the Redox measurement has been dealt with
in the MoreBioFilteration section. Simply
put, the Redox measurement indicates the
degree of chemical reactions (i.e. reduction
and oxidization) that are critical to the
decompositions in the denitrification cycle.
The measurement is in voltage. However, there
is not a single number that all the books
can agree on. Click MoreBioFilteration to review the discussion.
On the previous page, we have also mentioned
that use of Ozonizer can distort your Redox
measurement severly. It can even double your
Redox measurement. Here, we would like to
describe the relationship between the Redox
measurement and Ozonizer, and the PINPOINT
ORP controller shown before.
Let us have another look of the ORP controller:
The Front Panel
To the left is a picture of the front panel.
It has a display screen on the top and a
display mode switch on the bottom right.
By switching the display mode, you can see
the corresponding values on the screen. Hi
mode shows the upper limit; ORP mode shows
the measurement from the probe, and LO mode
shows the lower limit.
If the measurement from the probe is outside the range bounded by the upper
and lower limits, the controller will switch
on or off the power to the units that are
connnected to it. When the controller is
interrupting the units, say an Ozonizer,
the one of the Hi or LO lights and one of
the OUT1 or OUT2 on the top right will be
on. The OUT1 and OUT2 lights illustrate that
the corresponding device is powered or not.
Setting the Range
For this American Marine product, you need
to decide the center value and the range
value in order to set the Redox levels for
the controller. First decide the two limits
that you want to target. Then find the average
value and use it as the Center Value (the
right white screw in the middle section).
The Center Value is in the range of 5 to
900 mV. You can use the display mode to see
the Hi and Lo values for the Center value
that you just set. The last thing that you
need is to set the Range. For this device,
you can set the range between 10 to 100 mV.
The Range Value that you actually set is
then between 5 to 50 mV. So if the Center
Value is set to be 300mV and the Range is
set to be 50 mV, the the upper limit is 350
mV and the lower limit is 250 mV. A screw
is included in the test kit for you to turn
the screws. Again you can always switch the
display mode to see what the current range
is. After you have set the values and you
have put your probe inside the water, switch
the display mode to ORP to see the current
reading. You may need to wait for a few minutes
for the reading to become stable.
The Back of the Controller
The back of the controller has two power
outlets, 110 VAC each, to be connected to
a maximum of two devices. The probe is also
connected to the back of the controller.
You must keep the probe either in the water
or inside the protective cap (with the sloution
provided) included. If the probe is exposed
to the air for about half-an-hour, the probe
will no longer be functional. That is, you
have just lost your probe! We have a few
customers made that mistake before. In fact,
this is true for all the pressure probes
that most of the aquariums use. So please
do not make that mistake.
When the ORP measurement is above the upper
limit that you have set, the OUT1 light and
the corresponding power outlet will be energized.
Similarly, when the ORP measurement is below
the lower limit, the OUT2 light and the corresponding
power outlet will be energized. Since the
Ozone gas increases the Redox level in the
tank, you would plug your Ozonizer into the
low control outler, OUT2. This is because
we only want the Ozonizer to turn on if the
Redox level is below the pre-set value. If
you have another unit that you want to be
controlled by the Redox level in your tank,
you can plug into the other outlet of the
device. But remember that this outlet is
the high control outlet. The high control
outlet is only energized when the Redox level
is above the pre-set value. That is, you
never plug an Ozonizer to the remaining high
control outlet. Otherwise, you will have
your Ozonizer turned on when the Redox level
is already too high!
For the details of its operation, you can
consult with your local pet shop and the
manual included with the device.
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© Wai's Aquarium Ltd, 2000, 2001. All rights
reserved.