How to choose a pond pump? When choosing a pump for your Koi Pond, there are many different factors to consider.
The pump must be able to properly aerate the water. It also must be able to properly operate all pieces of the filtration system, from the filter to the UV Sterilizer, and anything else connected to your pond. The pump must be able to operate in a wet environment, either externally or submerged, and it must also be able to push water through all the twists and turns of the plumbing system.
To determine how much water your pump should move, it is first necessary to figure out how much water is in your Koi Pond. To determine how many gallons of water are in your fish pond, multiply the cubic feet of water by 7.48. It is this total volume that must be moved through the filtration system at least once per hour. Keep in mind that the entire pond must be aerated, not just the return area. It may be necessary to oversize the pump by quite a bit to add additional outlets. These can be plumbed to prevent stagnant flow, and may be a necessity on larger ponds.
Submersible pumps are the more common of the pumps. They can be simply dropped into a pond with an outlet plumbed to external waterfalls, fountains, or filtration systems. They can also be included on submersible filtration systems, and are often attached to decorative fountains. External Pumps are generally more powerful, and may run with less electrical cost. They must be plumbed in a dry location, and must be carefully chosen, as they must be manufactured to run in wet locations. A water-proof enclosure may have to be constructed to keep the external pump dry, depending on manufacturer’s specifications.
Pump Charts and Head Pressure are two foreign terms to most Pond Owners. Pump Charts are included with most Pumps, and show how much water the pump moves based on how much head pressure is applied. This is important because in order to operate a filtration system effectively, the pump must move the entire volume of water through the filter each hour. Head Pressure is a generic term for friction loss through pipes, tubing, and fittings. Without getting into advanced physics, you can calculate basic head pressure by adding a foot of head pressure for every foot of straight pipe or tubing, and for every fitting used. Always oversize the pump, and always attempt to turn move the entire volume of water through the filtration system at least once per hour.
As long as the proper amount of water is moved, the pump choices are less meaningful. There are minor differences in electrical consumption amongst pump manufacturers, but it should definitely be checked. There are definitely manufacturers with a good reputation, and as with most things, you tend to get what you pay for. Always be wary of excessively inexpensive pumps, as it is the centerpiece of your filtration system. The most important thing is to choose a pump that will run your system effectively.