To calculate the volume of the tank in litres, calculate the volume of the tank in cubic centimeters.
The volume of the tank can be calculated using simple geometric formulae such as length x breadth x height in case of rectangular aquarium or cubic aquariums.
The value in cubic centimeters should be divided by 1000. This will give the amount of water in litres.
For instance, a tank which is 60 cms long, 30 cms wide and 30 cms high will have a volume of 54 litres.lu