Pond Pump
Features such as waterfalls, streams and fountains add a whole new dimension to a garden or fish pond. All of these features require a pond pump to function correctly. There are numerous types of garden pond pumps available on the market. Selecting the right pond pump involves far more than finding a brand name or a good deal on the price. There will be some math involved in this process and one must also ensure that their safety is properly considered. After all, installing a garden pond pump means installing an electrical device in water which can be very dangerous if done incorrectly.
Pond Pumps and Safety
Before even getting started, one must make certain that they have the correct hardware for the job where safety is concerned. The garden pond pump should only be powered by an outdoor outlet unless it is a solar pond pump, in which case it will be solar powered. This outlet absolutely must have a Ground Fault Interrupter (GFI) installed on it. The GFI is a device which most people have seen on their bathroom outlets. These devices serve to break the circuit when water comes into contact with any electrical device. Without such a device, safety cannot be guaranteed.
One must also make certain that their outdoor outlet is a proper distance from the pond. A minimum distance of 6 feet is desirable though a distance of 10 feet is better still. This ensures that the outlet does not come into contact with the water when one is working on the pond pumps or filters. Given the proper safety equipment, it's time to proceed with selecting the garden pond pump!
Pond Pump Power - Water Quantity
Pond pumps are rated according to how much water they can move over a given time. In the case of smaller pond pumps, they will carry a rating listed as GPH which stands for Gallons Per Hour. This rating refers to the amount of water that the pump can move in one hour over a height of one foot. Therefore, if one's garden pond pump will be carrying the water more than a foot in elevation, one must take this into consideration when purchasing a pump.
Solar pond pumps are not very powerful and generally solar is only used to power a pond fountain pump. Very powerful pond pumps are rated in horsepower. These ratings - and occasionally GPH ratings, as well - are sometimes referenced to a chart provided by the manufacturer. These charts make it easier to determine how much water the pump will actually move in any given situation. Some stores will have this information listed generically, as well, which can help one to select a pond pump with enough power for the job.
Pond Pump Location - Above and Below
Some pond pumps are stationed above the water and some submerged. Each has its own particular advantages and disadvantages.
Above water pumps are very easy to maintain and troubleshoot. They're also kept clean of many of the pollutants such as sand and gravel that may have a negative impact on the performance of submersible pumps. These garden pond pumps, however, can be very pricey and the more powerful units may generate a lot of noise. This noise, of course, can detract from the effect of the water features they power and make the entire environment much less attractive.
Submersible pumps are more popular for small ponds than their surface-mounted cousins. These pond pumps are placed directly into the water where they operate almost silently. Of course, if there are problems with these pumps one must go through the hassle of pulling the pump out of the water to repair it and there is the hazard that the pond pump may gradually break down without it being apparent to the owner until it's too late.
Submersible pond pumps are also susceptible to contaminants floating in the pond water. There are pumps available that operate via magnetic engines. These are preferable to the older pumps. The older pumps required oil and coolant to operate properly. If the garden pond pump happened to have a failure which resulted in a rupture, this pollutant could easily end up in the water. Oils can interfere with oxygen exchange and present a poison hazard in and of themselves to anything living in the water. The magnetic pond pumps do not suffer from this drawback and, therefore, have become very popular with pond owners. Magnetic drives are very simple and, because of that simplicity of design, there is very little to go wrong in these devices.
Some pond owners attempt to use swimming pool pumps in their fish ponds. This is generally not recommended. A swimming pool is a much cleaner environment than a fish pond and those pumps are not designed to deal with the particulate pollution that characterizes fish ponds. Purpose-built pumps are the best choice.
Pond Pump Math
The amount of work done by the pond pump depends both on the height and the distance the water must be carried. For every 10 feet of horizontal distance the water must be moved one should figure in a height of 1 foot. Total height is determined by measuring from the top of the pond pump to the top of the waterfall or fountain. For example, if one's waterfall is one foot above the ground and their pump is located at the bottom of a three-foot deep pool, the water must be raised four feet to fill the waterfall.
Where the size of the waterfall or stream is concerned, every inch of width is the equivalent of 150 gallons over the course of an hour. A waterfall with a 5 inch spillway, for instance, will require a pond pump that produces 750 gallons per hour in raw flow.
The garden pond pump should circulate the pond water at least once per hour. To determine the volume of one's pond, the formula is (length * width * depth). If the pond is circular or odd-shaped, break it down into small rectangles to figure out the volume. For every square foot of volume there are 7.5 gallons of water. So, a pond that has a volume of 100 cubic feet will contain roughly 750 gallons of water. Most ponds, of course, are much smaller than this. From this figure, one can determine the GPH rating needed for proper circulation of the water.