The pump is the heart of most water features. Streams, fountains, waterfalls and filters all work because a hidden pump is circulating the water. Most water features are run with underwater or submersible pumps. External or in-line pumps are generally used for larger scale water features.
Submersible pumps are advantageous for several reasons. They disappear to the bottom of the pond, operate silently, require little maintenance and do not require priming.
Submersible pumps can be divided into 2 categories; general purpose pumps and high volume or lift pumps.
General Purpose Pumps
General purpose or “fountain” pumps are used for small to medium sized fountains and small waterfalls. They also function well as circulation and filtration pumps for small to medium sized ponds.
Most have attachments available that are designed for running small fountains and waterfalls.
Before choosing an all purpose pump it is important to know the volume of water the pump will need to move. The pump should be able to circulate the entire volume of water in the pond every 2 to 3 hours.
There are a number of additional demands that affect the flow rate requirements for the pump. These include, filters, fountains, spouters and waterfalls. The flow rate is measured in gallons per hour (GPH). About 150 to 250 GPH must be added to the pump’s flow rate for each of the options listed above. Always oversize rather than undersize the pump.
Once the GPH rating is known you can begin to compare the various features of the pumps available in the capacity you need. These include, the types of attachments and filters included, power consumption & cost to operate as well as electrical cord length and warranties.
Location of pump:
Install the pump in the deepest part of the pond. The best circulation is achieved when the water moves from one end to the other.