If you've recently bought a home in Southwest Florida and discovered you have an "ATU" instead of a conventional septic system, you likely have questions. Here's everything you need to know — including why ATUs require certified maintenance and what happens if you skip it.
What Is an Aerobic Treatment Unit?
An aerobic treatment unit (ATU) is an advanced septic system that uses oxygen to treat wastewater more thoroughly than a conventional anaerobic septic tank. Where a standard tank relies on settling and slow bacterial digestion, an ATU adds an air injection system that creates a more aggressive biological treatment process — producing significantly cleaner effluent.
How Does an ATU Work?
Most ATUs process wastewater in three stages:
- Pre-treatment chamber — Solids settle out, similar to a conventional tank
- Aerobic treatment chamber — An air pump injects oxygen, promoting rapid growth of aerobic bacteria that consume organic matter efficiently
- Clarification and disinfection — Treated effluent is clarified and disinfected with chlorine tablets before discharge to a drain field or spray system
Why Are ATUs Required in Some Areas of Southwest Florida?
Florida's environmental regulations require enhanced treatment in several situations — particularly on properties near wetlands, mangroves, tidal areas, canals connected to navigable waters, Charlotte Harbor, Estero Bay, or other protected estuaries. They're also common on small lots where setbacks make conventional systems difficult to install properly.
ATU Compliance Is Not Optional in Florida
Florida law requires that ATU systems be maintained under a service contract with a certified provider. Inspections are required three times per year. Failure to maintain your ATU can result in county fines, enforcement action, and a requirement to replace the system at your expense.
ATU Brands We Are Certified to Service
Certified Septic is certified to service virtually every ATU brand used in Southwest Florida — including Hoot, FujiClean, Delta, Fast, Norweco, Ecoflo, JET, Anua-Pura, Clearstream, Hydro-Action, Orenco, Aqua Safe, and Aqua Aire. For more detailed ATU information, visit our dedicated site at atuservices.com.
What Does Each ATU Service Visit Include?
- Aerator inspection and performance test
- Chlorinator inspection and tablet refill
- Alarm and control panel check
- Effluent quality assessment
- Spray head inspection (where applicable)
- Compliance report filed with Lee County or Charlotte County on your behalf
Need an ATU Service Contract or Inspection?
We handle all required compliance documentation and county filings — so you don't have to. Call us to get set up with a maintenance contract or to transfer your contract from another provider.
Call 239-510-4040