Some Useful Calculations. Enter the details then press the = button for the answer. Fish Tank Volume (litres)   Enter the tank length in cm Enter the tank width in cm Enter the tank height in cm litres     Fish Tank Volume (gallons)   Enter the tank length in cm Enter the tank width in cm Enter the tank height in cm gallons Litres to Gallons   Litres UK Gallons     Gallons to Litres   UK Gallons Litres     Inches to cm   inches cm     Square inches to square cm   Square inches Square cm     Square cm to square inches   Square cm Square inches     Cubic cm to cubic inches   Cubic cm Cubic inches     Cubic inches to cubic cm   Cubic inches Cubic cm     Square yards to square metres   Square yards Square metres     Square metres to square yards   Square metres Square yards     Ounces to grams   Ounces Grams     Grams to ounces   Grams Ounces     Pounds to kilogrammes   Pounds Kg     Kilogrammes to pounds   Kg Pounds