A water garden is a delicate and beautiful ecosystem that needs to stay properly balanced in order to thrive. Many components make up a water garden’s body, and at the heart of it all is the pump – keeping your entire garden pond healthy and happy.
Pumps move water from the reservoir pool to the header pool, lifting it in the process. (Most pumps run continuously and are maintenance-free and durable.)
Photo Credit: ©2001 Dolezal Publishing/John M. Rickard
The best choice for most water features is a submersible pump.
Photo Credit: ©2001 Dolezal Publishing/John M. Rickard
For complex water features, or for sites where maintenance access is restricted, choose an aboveground pump model (preferably enclosed in weatherproof housing).
Photo Credit: ©2001 Dolezal Publishing/John M. Rickard
Besides powering fountains and streams, pond pumps circulate water through pipes to submerged filters and skimmers, where it’s cleaned and reused, over and over. A pump also comes in handy when it’s time to clean the pool or pond – just attach a hose to the pump’s cleanout outlet and it will pump out the water for you. Yet, while the importance of a pond pump is great, this crucial piece of equipment is relatively easy to install, adjust and maintain.
Most residential water gardens use a submersible, underwater pump. It sits on raised legs or on a platform at the bottom of the pond to reduce the hazard of sediment and debris clogs. The pump draws water through an intake pipe and a filter screen, which catches debris that could otherwise clog and damage motor parts, then pushes it to another location through a pressurized delivery pipe. Surface-mounted pumps, located in concealed enclosures aboveground and away from the feature, are more common in water gardens with large streams and multiple elements, or those that cover a large area.
A pump’s size is based on its capacity, which is measured in gallons per hour (GPH). Some pumps’ flow rates may also be listed in gallons per minute (GPM). If your pump needs to lift water a considerable height (to operate a waterfall, for example), also consider its pressure of flow rate, or head height. Moving water uphill, for some distance or to deliver a broad fountain pattern typically requires pumps with higher GPH and pressure ratings. As a general rule of thumb, 100 percent of a pond’s volume should be circulated in an hour. (The more circulation, the healthier the pond.)
Before selecting a pump for your water feature or garden pond, you need to know its purpose. Some units, for example, deliver a high volume at low pressure, which is best suited for streams. Others offer a low volume at high pressure, which is better suited for fountains. Understanding the purpose of a particular pump will help you pinpoint the correct unit for your needs. (Pump manufacturers have simplified the process by offering compatible piping and related components to the different pumps available. Use only those components designed and rated for outdoor and underground use.) When choosing a pump, follow these steps:
- Calculate the volume of water in your pond or stream by multiplying its average length, width and depth. The pump’s flow rate in GPH should equal or exceed the total pond volume. (Don’t worry – even large-volume pumps are of modest size.)
- Choose a pump that’s purpose fits your needs and that has raised feet around its intake to reduce the potential for sediment clogs. (The best choice for most water features is a submersible mulching pump that chops up debris rather than clogs and stalls. High-efficiency models are designed to use less power and are most reliable.) Plan to install it in a skimmer intake box or mounted on a raised platform. (To install a submersible pump, follow the steps shown in the pictures at the end of this article and described in their captions.)
For complex features, or for sites where maintenance access is restricted, choose an aboveground pump model. Locate it near a power supply, close to the intake (within 5 feet of the water intake fixture). If needed, enclose it in weatherproof housing. Bury all recirculating pipe, keeping it easily accessible, and attach a check valve to prevent siphoning.
- If installing a fountain, calculate the height and diameter of your desired spray pattern. Check information contained with the spray head assembly, as most fountain packages provide general pump guidelines.
- Check the information on the housing and package for the pump’s electrical requirements, the necessary size and type of piping and compatibility with accessories.
Big or small, a water feature is only as good as the pump that keeps it going. Taking the time to understand the purpose of the pump you need, as well as how to properly install it, is critical for a healthy, balanced and beautiful ecosystem.
Recirculating Pump Installation
Recirculating Pump Installation - Step 1
Locate a skimmer or intake box at the garden pond’s edge and opposite the point of water entry into the pool. (Locating it in this manner means that the water will circulate throughout the pond, prevent stagnation and limit algae growth.) Excavate a shallow trench for the recirculating pipe, extending it from the skimmer to the pump, then to the discharge.
Photo Credit: ©2001 Dolezal Publishing/John M. Rickard
Recirculating Pump Installation - Step 2
Use two-part PVC primer and glue to cement all junctions of PVC pipe in the recirculating loop. Allow the glue to dry thoroughly. (Plan to pressure-test the entire system before you fill trenches and excavations.)
Photo Credit: ©2001 Dolezal Publishing/John M. Rickard
Recirculating Pump Installation - Step 3
Install an O-ring compression fitting to the skimmer or intake box and to the outflow box or discharge pipe. Use the appropriate adhesives, fastening materials and fittings recommended by the equipment manufacturer.
Photo Credit: ©2001 Dolezal Publishing/John M. Rickard
Recirculating Pump Installation - Step 4
Position, mark, excavate, install and level the skimmer or intake box. The top lip of skimmer intakes should be positioned 1-3 inches above the future water level and at least 6 inches above the site’s finish grade.
Photo Credit: ©2001 Dolezal Publishing/John M. Rickard
Recirculating Pump Installation - Step 5
Attach the check valve to the pump, place the pump into the skimmer box and use stainless steel hose clamps to join the outflow hose to the recirculating pipe that leads to the discharge at the header pool or waterfall. Tighten all connections.
Photo Credit: ©2001 Dolezal Publishing/John M. Rickard
