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Aquarium Tank Volume Calculator

Calculate your aquarium volume in gallons and liters. Get fish stocking recommendations based on tank size and shape. Perfect for planning your aquatic paradise!

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Tank Dimensions

inches
inches
inches

Enter tank dimensions to calculate volume

Understanding Aquarium Volume

Why Accurate Volume Matters

Knowing your tank’s exact volume is crucial for:

  • • Proper medication dosing
  • • Water conditioner amounts
  • • Fertilizer dosing for planted tanks
  • • Determining appropriate bioload
  • • Filter and heater sizing

Tank Shape Differences

Different tank shapes hold different volumes:

  • Rectangular: Standard calculation, most common
  • Bow-Front: Curved front adds ~10% more volume
  • Cylindrical: Uses circular base area formula

Frequently Asked Questions

Why subtract 10% for decorations?

Decorations, substrate, rocks, and equipment displace water. We subtract 10% to get a more accurate usable water volume for dosing purposes.

Is the inch per gallon rule accurate?

It’s a starting guideline, but not perfect. Consider fish body shape, activity level, territorial behavior, and waste production. Research each species specifically.

Can I stock to maximum capacity?

We recommend stocking below maximum capacity. This provides buffer for fish growth, better water quality, and less stress on your filtration system.

How do I measure an irregular tank?

For irregular shapes, measure the maximum dimensions and select the closest shape. You can also fill with a known volume of water using a measuring container.

Aquarist Reviews

“Perfect for dosing medications! Finally got the exact volume of my bow-front tank. The fish stocking guide is really helpful too.”

- Sarah M.

“Used this before setting up my 75-gallon reef tank. The accuracy helped me dose additives perfectly from day one!”

- James K.

“Great tool for beginners! The stocking recommendations kept me from overstocking my first tank. All my fish are thriving!”

- Emily R.