Aquarium Water Volume Calculator

When buying a new fish tank, or, when considering whether or not you can add more fish safely to your current tank, it’s important to first know how much water volume your tank will hold.

We often get asked questions from our customers on this topic - and that’s because it’s extremely important for a number of reasons, including:

Knowing how many fish you can safely keep in your tank
Understanding how to treat the water with various dosages of chemicals
Awareness of how often you should change or refresh the water to keep your fish healthy and happy.

To help you either decide on the size of aquarium you require, or to calculate whether you can home a brand new fish, we’ve developed a handy interactive tool, which allows you to calculate just how much water your aquarium can hold.

Select Tank Shape & Measurement

Enter Dimensions below

Width (cm)

Length (cm)

Height (cm)

UK Gallons

US Gallons

Litres

Disclaimer: The above calculator is a tool which calculates the approximate capacity of water volume in your fish tank. It is designed to be used as a guide for this purpose only. Those using this tool for tank treatment do so at their own risk. Always follow the manufacturer’s instructions, and consider factors such as aquarium contents (substrates, ornaments) as well was water level and glass thickness.