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Environment

Aquarium Volume Calculator

Calculate aquarium water volume, net usable capacity, and a simple stocking guide from tank dimensions.

External length
cm
External width
cm
External height
cm
Gravel depth
cm

Real-time Results

Gross Volume (Liters)
200.00L
Gross Volume (Gallons)
52.83gal

Detailed Stocking Analysis

Realistic view of your setup

ItemValue
Estimated Net Water180.00 L
Max Safe Fish Length120.00 cm

Why Choose Aquarium Volume Calculator

Easily calculate the true water volume of your aquarium and estimate how many fish you can safely keep. This calculator accounts for substrate depth and typical decor to give you a realistic net volume.

  • Calculates both Gross and Net water volumes
  • Converts between Liters and US Gallons automatically
  • Provides a basic safe fish stocking guideline (cm of fish per liter)

How to Calculate

  1. 1Measure and input the length, width, and height of your tank in centimeters.
  2. 2Input the average depth of your substrate (sand or gravel).
  3. 3View your gross volume and estimated actual net volume.
  4. 4Check the 'Max Safe Fish Length' to avoid overstocking your tank.

Frequently Asked Questions (FAQ)

What is the difference between Gross and Net volume?

Gross volume is the mathematical maximum capacity of the empty glass box. Net volume is the actual amount of water it holds after you add substrate, rocks, wood, filters, and leave a gap at the top. Net volume is usually 10-20% less than Gross.

How is the Max Fish Length calculated?

A traditional basic rule of thumb is '1 cm of adult fish per 1.5 liters of net water' (or 1 inch per gallon). This calculator uses the net water volume to give you a safe baseline. However, heavy waste producers (like goldfish or cichlids) need much more space.

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