These systems use a media filter chamber to contain the aerobic treatment process. The media can include sand/gravel, peat and textiles amongst other things. These systems achieve secondary or advanced secondary treatment and are well suited to tertiary treatment if required or desired (additional disinfection by chlorine or UV).
Media filter 1
Media filter 2
Benefits
- Some off-the-peg systems available
- Cope better with fluctuations in input
- Produce a high quality effluent
- Some well accepted by council
Drawbacks
- Can be more expensive
- Construction can be tricky
- Can under some configurations (eg recirculating) achieve high levels of nutrient reduction (important for sensitive receiving environments like waterways)
- If they fail it can be expensive and difficult to replace the media
- Council may require extensive monitoring of some designs (eg peat beds)