This calculator will help you to estimate the cost of operating any
given electrical pump, based on the average KWH (kilowatt hours)
used per day, and on the average cost per KWH charged by your
electric company.
Spare Me! Keep a spare air pump or water pump on hand for emergencies. If your pump ever stops, do not feed your Koi.
Consider using seperate water pumps for your waterfall and filter. This way you will always have a backup, and you can save energy.