Underground

Compact sewage treatment with GRAF’s quality advantage.

GRAF purification systems, with patented technology, satisfy more than 450,000 customers in more than 70 countries for more than 15 years. GRAF Australia develops and markets sustainable underground septic solutions that preserve the environment and make use of recycled elements.

The method employed by GRAF’s underground septic tanks is pretty simple – all the wastewater from the home or building goes into the tank and then gets broken down by bacteria. The solid waste sinks to the bottom and forms what’s called “sludge,” while the liquid waste rises to the top and forms a layer of “scum.” The liquid waste then flows out of the tank into a drain field, where it gets filtered through layers of soil before returning to the groundwater. 

By entrusting your purification solutions to GRAF, you are choosing first-class service, proven global experience and a Made-in-Australia product.

Carat Septic Tank With Baffle

Dual chamber septic treatment tank, suitable for volumes of 2700 to 6500 litres.

Carat Septic Tank Without Baffle

The simple septic holding treatment tank, suitable for volumes of 2700 to 6500 litres.

Carat XL Septic Holding Tank

The Carat XL Septic Holding Tank is the perfect solution for unsewered areas with maximum volume requirement of 10000 litres.