Aquarium planning

Litres and gallons conversion table

Compare litres with both gallon systems so imported aquarium information does not get misread.

Photorealistic image of aquarium rocks, plants and tropical fish

Two gallon systems, one unambiguous litre column

UK imperial gallons and US liquid gallons are different units. The table shows both so imported product information and online advice can be compared without silently switching definitions.

LitresUK gallonsUS gallons
51.101.32
102.202.64
204.405.28
255.506.60
306.607.93
408.8010.57
5011.0013.21
6013.2015.85
7516.5019.81
8017.6021.13
9019.8023.78
10022.0026.42
12026.4031.70
15033.0039.63
18039.5947.55
20043.9952.83
25054.9966.04
30065.9979.25
40087.99105.67
500109.98132.09

Constants used

UK imperial gallon
4.54609 litres.
US liquid gallon
3.785411784 litres.
Photorealistic image of aquarium rocks, plants and tropical fish

Convert the source figure into litres first when the gallon definition is unclear.

Avoid a common error

Traditional tank names such as “10 gallon” or “55 gallon” are frequently US-market descriptions. A UK reader who interprets them as imperial gallons will overstate the corresponding litre volume. Check the source market or manufacturer data.

The two gallon systems

UnitLitres
1 US liquid gallon3.785411784 L
1 UK imperial gallon4.54609 L

Because the imperial gallon is larger, the same aquarium has a smaller number of UK gallons than US gallons. Keeping “US” and “UK” beside the result is safer than writing only “gal”.

Useful reference conversions

LitresUK galUS gal
40 L8.810.6
60 L13.215.9
100 L22.026.4
200 L44.052.8