CENTRIFUGAL PUMPS
"Out-of-Pond" Pumps
Few things can be as confusing to a pond builder as choosing a pump. There are many different sizes and styles of pumps. We will try to help you understand the differences between pumps and how to select the best one for you. Many dealers and home improvement stores choose pumps based solely on price because they want to sell you a pump as cheap as possible. The problem is that while "cheap" pumps may work fine to pump out your boat or basement now and then, they will not last when used in a continuous duty operation like water gardening. Always choose a pump that is rated for continuous duty operation. While these pumps may cost a little more to purchase initially, they will last much longer and actually save you money in the long run.
Be careful when comparing pumps. With today's pumps, HP ratings mean nothing. Always compare GPM pumped versus amp draw. To calculate the operating cost of an electric motor use the following formula:
AMPS x VOLTS (115 or 230) = WATTS x HRS PER DAY OF OPERATION / 1000 x COST PER KILOWATT HOUR
Following are some pump operating
costs. Figures are based on 115 volt, 24 hour operation and a cost per
kilowatt hour of $0.09.
Operating cost per day for a pump drawing:
2.0 amps = $0.49, 5 amps = $1.24, 8 amps = $1.98, 10 amps = $2.48
