To calculate the volume of your water body and thus determine the size of Water Wych that is best for your pond or water feature, use one of the formulas given below. Remember, you cannot overdose with Water Wych - a larger one will work more quickly and last longer!
For rectangle and square ponds
Basic Formula:
Length x Width x Depth (measured in feet for conversion to gallons or metres for conversion to litres) x conversion factor.
Imperial Gallons
Length x Width x Depth (in feet) x 6.25 = Imp Gals.
US Gallons
Length x Width x Depth (in feet) x 7.5 = US Gals.
Litres
Length x Width x Depth (in meters) x 1000 = Litres.
Gallons to Litres
Imp Gal=4.546 Litres. US Gal = 3.7854 Litres.
For circular and oval ponds
Basic Formula:
Radius x Radius x Average Depth (measured in feet for conversion to gallons or metres for conversion to litres) x conversion factor.
Imperial Gallons
Radius x Radius x 3.142 x Average Depth (in feet) x 6.25 = Imp Gals.
US Gallons
Radius x Radius x 3.142 x Average Depth (in feet) x 7.5 = US Gals.
Litres
Radius x Radius x 3.142 x Average Depth (in meters) x 1000 = Litres.
Gallons to Litres
Imp Gal=4.546 litres US Gal = 3.7854 litres