SKETCH of a typical aerobic treatment unit tank, aerator, chamber AEROBIC Septic System Maintenance Procedures

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Aerobic septic system maintenance and cleaning procedures: maintenance Guide for Fine bubble aeration septic systems.

This ATU system article series provides designs and products for aerobic septic treatment units (ATUs) for onsite waste disposal, also called fine bubble aeration systems. We address aerobic septic system design, features, inspection, repair, and maintenance. Product sources are also listed.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

AEROBIC Septic System Maintenance Procedures & Products

SKETCH of a typical aerobic treatment unit tank, aerator, chamber

Maintenance of Aerobic Septic Systems - How to Care for An ATU

You can reduce problems with your ATU and extend the system life by performing basic maintenance. Also see ATU Suppliers.

[Click to enlarge any image]

Homeowners can reduce the operating cost of any septic system by conserving water use.

An aerobic system retrofit may also extend the life of a drainfield - but be sure to read the caveats described in the next section on using an ATU to extend drainfield life.

Using an Aerobic System to Extend the Life of a Drainfield

An aerobic system might be retrofitted to a conventional septic system in an attempt to extend the life of a conventional drainfield. Also, adding aeration or oxygen to a septic system may boost aerobic bacterial action in the biomat, improving the drainfield function. But it's not quite that simple.

We would look closely at any proposals to make this "improvement" to a conventional septic system. One reader wrote that their installer wanted to simply install an aerator in the original one-compartment septic tank.

Our opinion was that unless a settlement chamber or tank outlet filter were installed the result of aeration and agitation in the primary single-chamber septic tank would be to push suspended solids out into the drain field where it would be clogged quite rapidly.

While there are a number of interesting pre-packaged advanced wastewater treatment systems on the market, a web search (in 2005 and again in 2006) does not turn up much on installation, operating, or repair costs.

The manufacturers argue that each site is unique so installation costs vary. OPINION: we suspect that as with any costly but necessary product, some vendors just don't want to give the bad news up front. When we collect more explicit septic system failure and maintenance cost data we will post it at this website.

Aerobic Treatment Unit ATU Maintenance Tasks & Schedule Chart

Below we quote an adapted version of Clearstream Wastewater System Inc.s List of Aerobic Treatment Unit ATU Maintenance Requirements & Schedule, rearranged to list items in order of frequency.

Clearstream & Other Aerobic Septic System ATU Maintenance Schedule, Tasks, & Costs [1]

Maintenance Task Schedule
in order of frequency
Typical cost [2][3] Comments

Sand filter & other ATUs in Australia

Check blowers, contact media, pipework, valves, diffusers, effluent clarity, sludge return, removal of excess scum, pump operation, supply of chlorine tablets

Every 3 months  

or as recommended by the manufacturer's service manual [3]

Check surge control weir Every 6 months Varies by state.

Florida:$200./yr maintenance + $50./yr permit

Texas: $200 - $600./ year
Free from the manufacturer for the first two years of operation [2].
Clean aerator filters Every 6 months to 2 years  

In our OPINION, new ATU owners should first perform maintenance on the earliest recommended schedule.

Depending on observations made at that time and provided that system usage level does not change, you may be able to extend out the service interval to longer periods.

Break up clarifier scum Every 6 months to 2 years    
Clean aeration diffuser Annually    
Pump sludge from aeration tank Every 2 - 5 years $250.+./ per pumpout;

Some readers report pumpout required every 6-months.

Australia government recommends tank pumpout every 4 years or more often depending on the permit's specifications.

Pump sludge from trash trap Every 2 - 5 years $535. ? Reported by FL reader to clear clogs & system backup
Repair or replace aerator Every 2 - 10 years $350. - $750. + labor, depending on pump model & components  
Additional aerobic septic system steps & costs
Check, replenish, install disinfectant tablets or chemical Monthly $200-$200. / year See AEROBIC SEPTIC DISINFECTANTS - Calcium Hypochlorite
Check, repair effluent disposal spray heads for above-ground disposal systems Every 4 months see AEROBIC SEPTIC SYSTEM MAINTENANCE COSTS See AEROBIC SEPTIC EFFLUENT SPRAY HEAD REPAIR
Aerobic septic alarm test Every 4 months 0 See AEROBIC SEPTIC ALARM SYSTEMS

Notes to the table above

Aerobic Septic Systems Installation, Operation, & Maintenance Manuals

[1] Clearstream ATU website, retrieved 3/21/2013, original source: . The company includes this important ATU maintenance notice:

[2] For the first two years form the date of purchase, your local installer, from whom you purchased your Clearstream System, will inspect your system on a routine basis for operational problems.

Service on Clearstream electrical and mechanical components will be performed at no charge, if such components are found to be defective. After the termination of the guaranteed service period, your local installer will make available a service policy for a nominal fee.

[3] Costs for ATU maintenance tasks are gleaned from reader email and a survey of septic maintenance company websites performed through September 2015.

CLEARSTREAM AEROBIC SEPTIC SYSTEM OWNERS MANUAL [PDF] Models 500NS - 1500N Owners Manual, Parts List, Flow Diagram, Installation Instructions, Design Drawings, Specifications, Service Policy, Warranty, Clearstream Systems, retrieved 2018/03/13, original source:

HOOT Septic Systems Homeowners Manual for the H-Series IPA & EPA NPDES Systems for Ohio [PDF], HOOT Systems LLC, 2885 Highway 14E, Lake Charles LA 70607 USA, Tel: 888-878-HOOT, Website: retrieved 2018/03/13, original source:

Hoot Models H-500-NPDES, H750-NPDES, H1000-NPDES MANUYAL - or give Hoot a call at 888 878 HOOT or see their website

NESC, AEROBIC TREATMENT UNITS: An Alternative Septic System [PDF]. Pipelines, Vol. 16 No. 3 2005, NESC, West Virginia University, retrieved 2018/03/13, original source:
Aerobic systems treat wastewater using natural processes that require oxygen. Bacteria that thrive in oxygen-rich environments break down and digest the wastewater inside the aerobic treatment unit as they are suspended in the liquid.

Oklahoma DEQ, AEROBIC SEWAGE TREATMENT SYSTEM MANUAL [PDF], Oklahoma Department of Environmental Quality, P.O. Box 1677 Oklahoma City, OK 73101-1677 USA Tel:(405) retrieved 2018/03/13, original source:


Also see installation and maintenance and test instructions at AEROBIC SEPTIC ALARM SYSTEMS

Reader Question: Will Rid-X type products benefit the sludge in my aerobic septic system tank?

(June 15, 2014) Gene said:
In a 3 tank aerobic system (sludge, aerator, pump) its my understanding that the sludge tank function is the same as in a conventional (drain field).

It seems to me that a rid x type product would be of benefit to add to reduce the sludge build up n increase the pumping interval
true/ false ?

Reply: do not use additives or treatment in septic systems

Except for specially-engineered aerobic treatment septic systems for which the designer and manufacturer specify that a particular chemical is required such as disinfectants

(see AEROBIC SEPTIC DISINFECTANTS - Calcium Hypochlorite),

eptic treatment additives are unnecessary, do not improve the system's function, in some cases can damage the system (such as by breaking up and sending solids out into the absorption system) and the use of at least some such products is actually illegal in many jurisdictions.



Continue reading at AEROBIC SEPTIC SYSTEM MAINTENANCE COSTS or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.

Or see these

Aerobic Septic System Articles

Suggested citation for this web page

AEROBIC ATU SEPTIC MAINTENANCE PROCEDURES at - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia


Ask a Question or Search InspectApedia

Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

HTML Comment Box is loading comments...

Click to Show or Hide FAQs

Ask a Question or Search InspectApedia

Questions & answers or comments about septic effluent disinfection systems - chemicals to use and others to avoid using

Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

HTML Comment Box is loading comments...

Technical Reviewers & References

Click to Show or Hide Citations & References

Publisher - Daniel Friedman