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Calculating Aquarium Volume

How Can I Figure Out How Much Water My Fish Tank Holds?

(The First Tank Guide)

Use this simple form to convert the dimensions of your aquarium (in inches or centimeters) to a close approximation of its volume (in both U.S. gallons and liters) quickly and easily. All you need is to measure your fish tank's length (from side to side), height (from top to bottom of the tank), and depth (from front to back) and you can figure out how much water your aquarium holds!

Tank Width:
Numbers only, please.
The width of an aquarium is the distance across the front.
Tank Height:
Numbers only, please.
The height of an aquarium is the distance from top to bottom.
Tank Depth:
Numbers only, please.
The depth of an aquarium is the distance from front to back.
Measurements are in: Inches
Centimeters

This form will convert tank dimensions for your rectangular fish tank in either centimeters or inches to both gallons and liters. This conversion form can help you to determine appropriate tank population, and whether you have enough space for the fish you are planning on getting.

The results from this form will be approximate due to possible errors, inconsistencies, or inaccuracies in your measurements, and due to both rounding and the use of approximated conversion values in the calculations. I am converting at 2.54 centimeters per inch, 231 cubic inches in a gallon, and 3.79 liters in a gallon if you wish to check the calculations yourself.

If your tank is not rectangular, such as a bowfront (sometimes called eurostyle) or hexagonal tank, you can use the average of the questionable dimension to calculate your volume. For example, if your hex tank is 10" wide at the narrowest and 14" wide at the widest, you can use the average of 12" for the width to get a good idea of the volume of your tank.




"I want to thank you for your time to answer my incessent questions. I have talked with you several times and have always taken your advice and learned from it. I love your website and visit it often. I enjoy my aquarium more than I ever thought I would, therefore I want to learn everything I can about how to maintain my tank to keep it healthy and beautiful. I apologize for taking up your time with my questions and I appreciate the wonderful information you have shared with me. Thank you again."
October 22, 2006
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"UGH, I wish I'd found your site sooner. We had conducted extensive research, asking friends who had tanks, asking the pet store and watching numerous YouTube videos about starting a new aquarium. None of them clearly explained cycling or establishing the biofilter as your site has. If I hadn't found your site I would continued dutifully using the Ammonia reducer and adding fish then be wondering why they kept dying when I exceeded the ability of the tank to self-regulate. I wish more sites/YouTubers would explain this and so many fish could be saved."
March 25, 2018
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