This online tool uses German standards to calculate the appropriate solution. For septic tanks this online tool uses 250 Liter per person per day to calculate the appropriate solution. However, wastewater parameters in your region (water consumption per day, organic load, etc.) may be different. Otto Graf GmbH suggests that you contact an authorized Graf wastewater specialist to make sure the correct parameters were taken into account for the sizing of your system. Otto Graf GmbH is not liable for any issues resulting from the use of this online dimensioning tool.