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Waste Water Treatment

Optum recommends the Biolytix and GRAF Eclean 20 waste water systems.

Optum recommends two systems for domestic on site waste treatment: The Biolytix system which uses natural organisms to break down waste, or the GRAF EClean 20 that provides low cost, reliable and effective effluent treatment.

The Biolytix


The Biolytix is an eco-friendly alternative to a traditional septic tank. Biolytix is a vermiculture (worm-based) secondary treatment wastewater system, which uses natural organisms to break down waste, resulting in treated, suitably clean water to simply soak into a dispersal field.

Biolytix tanks


The Biolytix is an ‘ecosystem in a tank’. It treats the wastewater without needing costly, large mechanical aerators to run, repair or replace, which results in up to 90% less energy being consumed than in most aerated sewage treatment systems, thereby reducing electricity costs.


Optum is an approved agent and installer for the Biolytix®. As with any wastewater or septic system, the Biolytix requires regular maintenance in order to function properly and maintain an optimum environment for the organisms that process the waste. A minimum of an annual service is required to make sure the system is working correctly and to uphold the product warranty.

The Biolytix is a worm-based system. The worms are what process the waste, so it is very important to keep them happy! The worms won’t process the following items, so they can’t be flushed into the tank:


If you can follow the above requirements, and you’re looking for an eco-friendly waste disposal system, which provides irrigation at the same time, a Biolytix will work for you.


To supply and install a Biolytix with a drip line irrigation dispersal field usually ranges from $15,000 – $25,000, depending on a number of factors, including the size and type of dispersal field and site location.


Further Information

Visit the Biolytix Website

Download a general brochure for the Biolytix system

Looking after your Biolytix. Information sheet on maintenance requirements.

Get in touch for more details.

Quality Products
Optum managed the installation process to our complete satisfaction and we would recommend the Biolytix system without hesitation.

GRAF EClean 20 Domestic On-site Waste Treatment

Optum will always use the highest quality products that will perform long term for our clients. With wastewater being a fundamental part of the rural homes and how it is taken care of in a safe and healthy manner, with minimum environmental impact, we recommend using the German designed Graf wastewater tank.

Energy efficient German technology that provides low cost, reliable and effective effluent treatment.

The Graf EClean 20 residential wastewater treatment system is designed in Germany, assembled and installed in New Zealand by wastewater experts.

  • Discharge easily exceeds OSET testing and relevant AS/NZ Standards
  • A proven, low maintenance system used in more than 40 countries and by more than 200,000 people worldwide
  • Designed to run on very low energy or solar power (.55 kWh/day = 10c approx.)
  • Treated water easily meets and often exceeds Council standards, despite varied inflow volumes
  • Compact and concealed, features a telescopic lid that sits flush with your lawn.
  • Easy to install with less excavation needed, and low power consumption to save you money
  • Allflow designs the entire wastewater system for you and handles the consent process from start to finish.

Features and benefits

Meets the appropriate standards
The Graf EClean 20 wastewater treatment system has been independently tested under the On-site Effluent Treatment national testing Programme (OSET NTP) and meets, and in many cases exceeds, the requirements of AS/NZS 1547:2012 and AS/NZS 1546.3:2008 relating to secondary effluent quality and performance. The Graf EClean 20 is also certified to AS/NZS 1546.1:2008 relating to the engineering and construction of the tank and associated fittings. Download the EClean 20’s Performance Certificate in the OSET NTP Trial 12, 2016/2017.

Low power use
The Graf EClean 20 Domestic wastewater treatment system is designed for minimal energy consumption and runs on approximately .55 kWh/day (about 10 cents.) The EClean system is suitable for isolated and off grid dwellings as it can be operated effectively on solar power.

Low maintenance
The Graf EClean 20 is a simple, one tank SBR (Sequential Batch Reactor) system that works using aeration and settling phases. Unlike other systems, there is no filtration, no mechanical moving parts in the treatment chamber, and no media required (live or artificial) which can be vulnerable to flooding – meaning there is very little than can go wrong, and minimal maintenance required.

Fully programmable system to suit any location
The Graf EClean 20 system is set up and run by a standalone control unit that can be installed in a preferred location. This unit contains the PLC, air blower and air valves, and allows custom system settings and diagnostics to be performed. It also features an automatic vacation mode that keeps the biological system alive and reduces power consumption when away on holiday.

Easy to install and operate
The Graf EClean 20 is a flat pack system that can be pre-assembled or assembled on site. The plastic injection moulded tanks are tough and durable and, unlike concrete systems, it’s lightweight. This makes installation easier and cheaper, as no crane is required, and the one large tank system means less excavation. There is also a smaller, separate disinfection tank.

Market leading warranties
Allflow is proud to offer market leading warranties: three years for installation, 15 years for the tank.

A better-looking system
Unlike some wastewater systems that protrude from the lawn, the Graf EClean 20 is fully concealed, and features a green telescopic lid that can be raised or lowered so it sits flush with the lawn. There is also the option of telescopic dome lids to allow system installation in areas of traffic, as these can handle the weight of up to 12-ton trucks. We offer the option of an EClean Concrete tank instead of a plastic moulded tank upon request.

Show Features & Benefits