Introducing the New AirOxi Aeration Tube: Fine Bubbles, Better Night-Time DO and Lower Maintenance
Updated
for 2026
In fish
and shrimp farming, a good aeration system is not simply one that produces a
lot of visible bubbles. Its real job is to maintain sufficient dissolved
oxygen (DO) throughout the pond, particularly during the late-night and
early-morning hours when oxygen levels are often at their lowest.
AirOxi is
introducing a new-generation aeration tube with an improved formulation,
developed after extensive trials and benchmarking against leading international
aeration tubes.
Quick Summary
The new
AirOxi aeration tube is designed to produce fine bubbles with easy airflow
at relatively low operating pressure. This combination can improve oxygen
transfer and help farmers maintain healthier dissolved oxygen levels,
especially during critical night and early-morning periods. The new formulation
is also designed to resist blockage better, helping maintain airflow for longer
and reducing the frequency of cleaning.
Why is dissolved oxygen so
important in fish and shrimp farming?
Dissolved
oxygen directly affects respiration, feeding, growth, stress levels and the
overall health of fish and shrimp.
Most
aquaculture farmers already understand DO because it is something they can
measure directly with a DO meter and express in mg/L.
As a
general operational target, many farmers try to keep pond DO above
approximately 4 mg/L, although the desirable level varies according to
species, stocking density, biomass, water temperature and culture system.
Higher DO
levels can provide an additional safety margin, particularly in intensive
culture.
What is
more important than a single afternoon reading, however, is how the pond
behaves throughout the night.
Why should farmers judge aeration
at 4 AM rather than 4 PM?
Don’t
judge aeration at 4 PM. Judge it at 4 AM.
This
simple rule explains one of the most important principles of pond aeration.
During
daylight hours, algae and other photosynthetic organisms can add oxygen to the
water. Because of this, a pond may show an apparently excellent DO reading in
the afternoon.
After
sunset, photosynthesis stops.
But
oxygen consumption does not stop.
Fish,
shrimp, algae, bacteria and other microorganisms continue consuming oxygen
throughout the night. DO therefore commonly falls progressively from evening
until the early hours of the morning.
A pond
may, for example, show a comfortable DO of 6–8 mg/L in the late afternoon,
yet approach much lower levels before sunrise if aeration capacity is
insufficient.
The real
test of an aeration system is therefore not how impressive the bubbles look
during the day.
It is:
What is
the DO at 3 AM, 4 AM or 5 AM when the pond needs aeration the most?
For more
practical information on managing dissolved oxygen and aquaculture aeration,
farmers can explore the AirOxi Knowledge Center and technical articles
on airoxi.com.
How do fine bubbles help improve
dissolved oxygen?
Fine
bubbles create a larger total air-water contact area and generally remain in
the water longer, giving oxygen more opportunity to dissolve.
Imagine
supplying the same quantity of air in two different ways.
If it
forms a few large bubbles, the total surface area between the air and water is
relatively limited.
If that
same air is divided into thousands of fine bubbles, the combined surface area
becomes much greater.
Fine
bubbles also generally rise more slowly through the water. This increases the
time during which oxygen can transfer from the bubble into the surrounding
water.
For the
farmer, however, the goal is not simply to produce the smallest possible
bubble.
The goal
is to achieve the right combination of:
- Fine bubbles
- Good airflow
- Low operating pressure
- Good oxygen transfer
- Uniform aeration
That
balance has been a major focus in developing the new AirOxi tube.
What is different about the new
AirOxi aeration tube?
The new
AirOxi tube uses an improved formulation developed to balance fine-bubble
formation with easy airflow and relatively low operating pressure.
During
development, AirOxi benchmarked its tube against leading international aeration
tubes.
The
objective was to understand not only bubble appearance but also practical
characteristics such as airflow resistance, operating pressure, bubble quality
and long-term performance.
The new
formulation has been developed around four main requirements:
- Fine and well-distributed
bubbles
- Easy passage of air through
the porous tube
- Efficient operation at
relatively low pressure
- Reduced tendency toward pore
blockage during long-term pond use
Farmers
looking to understand the different AirOxi tube options can also refer to the practical guide to
choosing the right AirOxi aeration tube.
Why is low-pressure airflow
important?
An
aeration tube should allow the required airflow without creating unnecessary
pressure resistance for the blower.
A very
fine-pore tube may appear attractive because it creates fine bubbles. But if excessive
pressure is required to push air through those pores, the blower has to work
harder.
At the
other extreme, a tube with very open pores may allow air to pass easily but
could produce larger bubbles.
The
engineering challenge is therefore to achieve:
fine
bubbles without excessive airflow resistance.
This
becomes increasingly important in commercial farms using hundreds or thousands
of metres of aeration tubing.
Even a
relatively small difference in operating pressure can become significant when
blowers operate for many hours every day.
AirOxi
offers different aeration tube designs for different blower and pond
requirements. Farmers can review the current AirOxi aeration tube range when planning a system.
How does better aeration help
maintain night-time DO?
Efficient
oxygen transfer helps the aeration system compensate for the continuous oxygen
consumption that occurs throughout the night.
A typical
pond DO pattern may look something like this:
|
Time of Day |
Typical DO Situation |
|
Afternoon |
DO may
be relatively high because of photosynthesis |
|
Evening |
Photosynthesis
stops and DO begins declining |
|
Midnight |
Fish,
shrimp and microorganisms continue consuming oxygen |
|
3–5 AM |
Often
one of the most critical periods |
|
Sunrise |
Photosynthesis
gradually starts again |
Actual DO
values will vary considerably from pond to pond.
That is
why farmers should not rely only on daytime readings. Periodic early-morning
DO measurement provides a much better indication of whether the aeration
capacity is adequate for the biomass being cultured.
If DO is
regularly approaching the lower acceptable range before sunrise, additional
aeration capacity, longer operating hours or better aeration distribution may
be required.
What does SOTR mean in an
aeration system?
SOTR, or
Standard Oxygen Transfer Rate, is a technical measure of how much oxygen an
aeration system can transfer into water under defined standard conditions.
SOTR is
useful to engineers and equipment designers when comparing aeration
technologies.
For the
farmer, however, the practical result is much easier to understand:
DO
measured in mg/L.
A farmer
does not need to calculate SOTR every morning. What matters is whether the
aeration system can maintain suitable DO throughout the pond, particularly
during periods of maximum oxygen demand.
Fine
bubbles, sufficient airflow and good bubble-water contact contribute to
effective oxygen transfer and therefore to better overall aeration performance.
Why does an aeration tube start
losing airflow over time?
Aquaculture
water contains algae, biofilm, suspended solids and other material that can
gradually accumulate on or inside the porous structure of an aeration tube.
This is
an important practical issue with porous aeration systems.
As pores
become restricted, farmers may notice:
- Reduced bubbling in some
sections
- Uneven air distribution
- Increasing pressure in the
air line
- Lower overall airflow
- Increasing need for cleaning
If
contamination remains mainly on the outer surface, cleaning may restore
performance relatively easily.
If
material penetrates deeper into the pores, restoring the original airflow can
become more difficult.
For this
reason, long-term resistance to blockage is almost as important as the initial
bubble performance of an aeration tube.
How is the new AirOxi tube
designed to reduce maintenance?
The new
formulation has been developed to reduce the tendency for contaminants to
penetrate and obstruct the porous structure while still allowing easy airflow.
The
objective is not to claim that an aeration tube operating in pond water will
never require cleaning.
All
aeration tubes eventually require maintenance.
Instead,
the objective is to achieve:
more
stable airflow + longer intervals between cleaning + easier maintenance.
Actual
cleaning frequency will depend on several factors, including:
- Water quality
- Algae and biofilm
- Suspended solids
- Stocking density
- Feeding intensity
- Pond depth
- Blower operating schedule
- Whether air is continuously
maintained in the tube
For a
commercial farm, reducing cleaning frequency can save labour and also reduce
periods when the aeration system is operating below its intended performance.
What should a farmer look for in
an aeration tube?
A farmer evaluating
an aeration system should look beyond the amount of bubbling visible at the
water surface.
The
important questions are:
|
Question |
Why It Matters |
|
Does it
produce fine bubbles? |
Helps
improve air-water contact |
|
Does
air flow easily through the tube? |
Reduces
unnecessary airflow resistance |
|
What
pressure does it require? |
Affects
blower load and energy use |
|
Is
bubbling uniform? |
Helps
distribute oxygen throughout the pond |
|
Does
airflow remain stable over time? |
Important
for long-term performance |
|
How
frequently does it require cleaning? |
Affects
labour and maintenance cost |
|
What is
the DO at 4–5 AM? |
Shows
whether the system is meeting the pond's real oxygen requirement |
The last
point is particularly important.
A pond
full of bubbles does not automatically mean the fish or shrimp are receiving
sufficient oxygen.
Measure
the DO.
How much aeration does my pond
actually need?
The
required aeration capacity depends on pond size, culture type, stocking
density, biomass, water depth and oxygen demand.
Using too
little aeration can create low-DO periods, while simply installing more tubing
or a larger blower without proper system design is not necessarily efficient.
Farmers
can use the AirOxi Aeration
Calculator to
estimate aeration requirements for their particular aquaculture application.
The
calculator can also help when considering tube length and blower capacity while
planning a new installation or expanding an existing pond.
What is the practical advantage
of the new AirOxi tube?
The new
AirOxi aeration tube has been developed around a simple engineering objective:
Fine Bubbles + Easy Airflow + Low Pressure + Better
DO + Lower Maintenance
For an
aquaculture farmer, these are not separate benefits.
They are
interconnected.
Easy
airflow at lower pressure can reduce unnecessary blower load. Fine bubbles can
improve oxygen-transfer conditions. More consistent airflow helps maintain
uniform aeration. Better resistance to blockage can extend the period between
cleaning cycles.
Together,
these characteristics are designed to help maintain the parameter that
ultimately matters most to the farmer:
dissolved
oxygen in the pond, particularly during the critical hours before sunrise.
So when
evaluating an aeration system, don't only look at the bubbles during the
afternoon.
Don’t
judge aeration at 4 PM. Judge it at 4 AM.
Plan Your AirOxi Aeration System
Explore
the AirOxi aeration tube range or use the AirOxi Aeration Calculator to estimate the aeration
requirement for your fish or shrimp farming application.
