Backyard ponds for decorative fish, water plants or just decoration add an exotic element to the back yard. Most backyard ponds require the movement of water to keep the fish, plants, and the water itself healthy and clean, and pond enthusiasts often accomplish this by including a fountain or waterfall as part of the pond's design.
This is not difficult to add and makes your backyard pond and garden area a delight for everyone who visits. The central element of fountains and waterfalls are the pond pumps, which circulate water from one end of the pond to the fountain, or to the uppermost region of your waterfall. It's important to locate pond pumps at the opposite end of the waterfall or fountain, to allow for the maximum amount of circulation. Although some pond fish are more hearty than others, koi are very delicate and require special attention, water circulation of some sort will be a virtual necessity of you plan on keeping koi in your pond.
Pond pumps are electrical, and require a waterproof cord which usually comes with pond pumps. The cord may be buried or hidden between the pond and the outdoor electrical outlet. Higher capacity pond pumps are required in ponds with fountains, because more pressure is required to lift the water. Pond pumps are installed under water, and generally do not create any distracting noise. A magnetic drive pump is better than a conventional pump, because it does not use coolants, and there is no risk of a seal breaking and polluting the water.
There are different sized pond pumps, and the size and horsepower you will need will depend on the size of your pond, and how many fountains and waterfalls you install. If you have multiple fountains or waterfalls, it may be desirable to install one pump for each, which allows you to purchase smaller pond pumps--and also gives you the advantage of having a backup so water circulation can continue if one of them should fail.