UK gallons
A UK gallon is a unit of volume used in the United Kingdom for measuring liquids such as fuel and water. One UK gallon is about to 4.54609 liters or 0.16054 cubic feet making it substantially larger than the US gallon.
Cubic Meters
A cubic meter is a metric unit of volume which is the equivelent space occupied by a cube with 1 meter on each of its sides.
Denoted by symbol "m³", it is a unit of measurement in the International System of Units (SI) and is generally used for larger volume measurements.