Selecting a Pump
From the smallest barrel garden to the largest koi pond, no water garden can survive very long without water movement. And for water movement, a pump is essential. The pump has been called the "heart of the pond" because it keeps the water circulating and the pond healthy. In addition, the most popular water features includes water movement.
A cascading, bubbling stream adds interest and serenity to the garden, while a waterfall can create a dramatic centerpiece. Fountains provide the additional benefit of aerating the water, essential for providing a healthy environment for fish. Water movement is also needed for filters that help keep the water clear.
To maintain a healthy pond, experts recommend circulating the water at least once every two hours. This means that, for a 1000 gallon pond, you will need to pump at least 500 gallons per hour. A 500 GPH, or larger, pump will be needed. Circulating the water once an hour is ideal.
The higher the pump must push the water, the less water will
be pumped. The term head height is used to indicate the rise,
measuring how high the water must be pumped for a particular
application. Every ten feet of tubing the water is pumped through adds resistance equal to one foot of rise, reducing pump flow.
When selecting a pump, look for the GPH at each head height, as well as the maximum height that the unit will pump. At maximum height (called max. head) the pump only puts out a trickle of water. Use the information provided to find a pump suitable for your needs.
Frequently Asked Pump Questions:
Q: What is the difference in magnetic drive pumps and direct drive pumps?
A: Magnetic-Drive (Mag-Drive) pumps have a motor that creates a magnetic charge to spin an impeller which creates water flow. These pumps are more energy efficient, however they don't produce as high of flow rates as direct-drive pumps. Direct-Drive pumps have a motor that directly spins a shaft which powers the impeller.
Q: What size pump do I need for my pond?
A: To maintain a healthy pond it is recommend to circulate your water every hour or at a minimum once every two hours. It can depend on the filtration system you have in you pond as well as your pond size. If you are using a filterfall you need to stick to the recommendation of once per hour or once every thirty minutes. For gravity flow and pressurized filters you may only need once every one or two hours. You will need to know the max flow for these type filters. For very large ponds over 4000 gallons you may not require as much circulation.
Q: What is Head Pressure?
A: Head Pressure is the force/resistance that the pump must overcome to push the water out at the end of the tubing. There is pressure from the vertical height to the discharge poing and there is also pressure caused by the tubing and fittings.
Q: Can the pump flow be adjusted?
A: Some smaller pumps come with a diverter valve or a flow control valve. In other pumps you will have to use a ball valve or a diverter valve in order to adjust the flow.