Guides
How Much Does a Fish Tank Weigh? 10, 20, 40, 55 and 75 Gallon Weights
Filled weights for 10, 20, 29, 40, 55, 75 and 125 gallon tanks, with water, glass and gravel broken down, plus how to check your stand and floor.
Read more →Fish Tank Weight Calculator
Weight
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Enter your tank dimensions to see the volume.
Did we solve your problem?
Estimate how heavy your aquarium will be when full. Enter the dimensions to get the volume, then convert it to the weight of the water.
How tank weight relates to volume
Fresh water weighs about 1 kilogram per litre, and a US gallon weighs about 3.79 kilograms. Find your volume in litres, then the water weight in kilograms is roughly the same number. Add the glass, stand, substrate and rocks for the total.
Weight of the water by tank size
| Dimensions (cm) | Litres | Fresh water (kg) | Salt water (kg) | Fresh water (lb) |
|---|---|---|---|---|
| 30 × 30 × 30 | 27 | 27 | 28 | 60 |
| 40 × 25 × 25 | 25 | 25 | 26 | 55 |
| 45 × 30 × 30 | 41 | 41 | 42 | 89 |
| 60 × 30 × 30 | 54 | 54 | 55 | 119 |
| 60 × 30 × 36 | 65 | 65 | 66 | 143 |
| 80 × 35 × 40 | 112 | 112 | 115 | 247 |
| 100 × 40 × 50 | 200 | 200 | 205 | 441 |
| 120 × 40 × 50 | 240 | 240 | 246 | 529 |
| 120 × 50 × 50 | 300 | 300 | 308 | 661 |
| 150 × 50 × 60 | 450 | 450 | 461 | 992 |
Calculated with the same formula as the calculator above. Values are rounded.
Water weight at a glance
Drag to fill a 60 by 30 by 30 cm (54 L) tank and see how much the water weighs.
50% full ≈ 27 kg of water (59.5 lb)
Formula
V = length × width × height Related calculators
Frequently asked questions
How do I work out the weight of a full fish tank?
Multiply your volume in litres by 1 kilogram, then add the weight of the glass, substrate and rocks.
How much does a 200 litre tank weigh?
The water alone weighs about 200 kg, and the loaded total is often 250 to 290 kg with glass and substrate.
Is saltwater heavier than fresh water?
Yes, slightly. Salt water is about 1.025 kg per litre, so add 2 to 3 percent for a marine tank.
Why does tank weight matter?
A heavy tank needs a stand rated for the full load and is best placed against a load-bearing wall.
What units can I use in this calculator?
You can switch between centimetres, millimetres, inches, feet and metres at any time. Enter all dimensions in the same unit and the result updates instantly.
Does the result include substrate and decoration?
The figure is the full internal capacity. Subtract roughly 10 to 15 percent for substrate, rocks and the gap you leave at the top to estimate the real water volume.
How accurate is this fish tank calculator?
It uses the exact geometric formula for each shape, so the result is accurate for the dimensions you enter. Measure the inside of the tank for the best accuracy.
Is this calculator free to use?
Yes. It is completely free, needs no sign-up, and works on phones, tablets and desktops.
Related guides
Learn the core ideas behind fish tank volume before or after using the calculator.
Size Guides
Standard Fish Tank Dimensions: 10, 20 Long, 29, 40 Breeder, 55 and 75 Gallon
Standard aquarium dimensions in inches and cm, footprints and filled weights, and how to tell look-alike sizes apart.
Read more →Guides
How Much Aquarium Substrate Do I Need?
Work out exactly how much gravel, sand or aqua soil your tank needs, the right depth, and how many bags to buy.
Read more →