One of the most common questions homeowners ask during servicing is:
“Should my HSTP be running all the time?”
The answer depends on which part of the system you’re talking about.
Many homeowners hear a constant humming noise coming from their wastewater system and assume something is wrong.
In reality, that sound is often a very good sign.
The Aerator Pump Is Designed to Run 24/7
In most Home Sewage Treatment Plants (HSTPs), the aerator pump operates continuously.
That’s right:
👉 24 hours a day
👉 7 days a week
👉 365 days a year
Unlike the submersible pump, which only operates when required, the aerator pump is designed to run constantly.
This is completely normal.
In fact, if the aerator isn’t running, that’s when you should be concerned.
What Does the Aerator Pump Do?
The aerator pump is one of the most important components in your HSTP.
Its job is to:
- supply oxygen to the aeration chamber
- support the biological treatment process
- keep beneficial bacteria healthy and active
- assist sludge return systems on many HSTP models
Without the aerator, the treatment process simply doesn’t work properly.
Why Does It Need to Run All the Time?
The secret lies in the bacteria.
Your HSTP relies on billions of naturally occurring aerobic bacteria to break down household wastewater.
These bacteria need oxygen to survive.
The aerator continuously supplies air into the treatment chamber, creating the perfect environment for these bacteria to thrive.
Think of it like keeping fish alive in an aquarium.
Turn off the air supply long enough, and problems begin.
The same principle applies inside your wastewater system.
Healthy Bacteria = Better Treatment
When the aerator operates continuously:
✔ Waste is broken down efficiently
✔ Treatment quality remains high
✔ Odours are minimised
✔ The system remains balanced
✔ Treated water quality is maintained
This constant supply of oxygen is one of the reasons HSTP systems achieve a much higher level of treatment than traditional septic systems.
What Happens If the Aerator Stops?
If the aerator pump fails:
- oxygen levels begin to drop
- bacteria become less effective
- treatment quality declines
- odours may develop
- system performance can deteriorate
This is why most HSTP systems are fitted with alarms.
The alarm is designed to alert you if there is an issue with critical components such as the aerator pump.
What About the Submersible Pump?
This is where some confusion occurs.
Unlike the aerator pump:
👉 The submersible pump should NOT run continuously.
The submersible pump only operates when treated water reaches a predetermined level inside the pump chamber.
The float switch activates the pump, which then sends treated effluent to the irrigation or land application area.
Once the water level drops:
👉 The pump switches off.
This cycle repeats as required.
How Can I Tell If My Aerator Is Working?
Most homeowners can usually tell by:
- hearing a steady humming sound
- observing air movement inside the aeration chamber (where visible)
- confirming the alarm is not activated
If the system suddenly becomes unusually quiet, it may be worth investigating.
Why Regular Servicing Matters
Because the aerator runs continuously, it is one of the hardest-working components in the entire system.
Over time, parts naturally wear.
Regular servicing helps identify:
- reduced air output
- worn diaphragms
- failing components
- electrical issues
before they become major problems.
At Maxfield’s Wastewater, we inspect aerator performance during every service to ensure your system continues operating as designed.
We Carry Replacement Aerators
One of the biggest frustrations homeowners face is waiting days or weeks for parts to arrive.
That’s why our service vehicles carry:
✔ Aerator pumps
✔ Submersible pumps
✔ Common replacement parts
✔ Components for multiple HSTP brands
In many cases, we can diagnose and repair an aerator issue during the same visit.
This minimises downtime and keeps your system operating properly.
Don’t Ignore a Silent Aerator
If your HSTP suddenly seems quieter than normal, or an alarm has activated, it’s worth having the system checked.
The aerator is the heart of the treatment process.
Without it, the bacteria that clean your wastewater cannot do their job effectively.
Speak with Jamie
If you’re unsure whether your HSTP is operating correctly, or you have concerns about your aerator pump, Maxfield’s Wastewater can help.
We service all major wastewater treatment systems throughout the Moreton Bay region and provide professional servicing, repairs, and advice.
Contact Maxfield’s Wastewater and speak directly with Jamie.
Maxfield’s Wastewater
Local. Reliable. Done Right.
