Water tank calculator

How much water do you use? Use our helpful calculator to find out.

Water Tank Calculator


ActivityTimes Per DayActivityLtr Per DayLtr Per Year
Shower15 Litres per minute
Bath150 Litres
Dishwasher30 Litres per load
Front Load Washing Machine80 Litres per load
Top Load Washing Machine100 Litres per load
Brushing Teeth with tap running5 Litres per person
Drinking, Cleaning, Cooking per person10 Litres per day, per person
Hand Basin Use5 Litres per time
Toilet Flush single6 Litres per time
Toilet Flush half3 Litres per time


ActivityTimes Per DayUnitsLtr Per DayLtr Per Year
Garden SprinklerGarden hose 15L /min.
Car Wash200 Litres
Hosing Hard Surfaces 15 litres per minute
Drip Systemlitres per hour
Filling poolSize in Litres

Size of water tank

Roof area (m3)Average Annual Rainfall (mm)Amount of rain harvested (litres)Minimum Tank Size
   Assume the tank can fill 3 times
per year (Depends on rainfall and usage patterns)

Total Per Annum

Calculation Summary

Litres per dayLitres per yearRain harvestedTank Size


To help calculate the size of water tank you need, Bushmans has created a tank calculator that allows you to input your water usage details and find the right tank for you.

To view the range of Bushmans Tanks available for purchase, please click here

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