Introducing the New AirOxi Aeration Tube: Fine Bubbles, Better Night-Time DO and Lower Maintenance

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.