Think of water as the lifeblood of your pond. It needs to circulate efficiently to distribute oxygen and organic compounds throughout. Water, even flowing in rivers, will naturally develop eddies and pockets where the water tends toward stagnation. These areas can become starved of oxygen, chemically out of balance, and promote growth of algae, mosquitoes and other pests. This water needs to move so it can absorb oxygen and distribute nutrients evenly in order to maintain a healthy environment. Just as in the human body, there’s really no efficient way to accomplish this task except through a pump.
There are two main types of pumps available to a hobby pond owner: submersible and centrifugal. Submersible pumps can be a cost effective choice for smaller ponds. They’re not unlike those pumps that sit at the bottom of swimming pools in the deep end. They’re silent, don’t bother anyone, and are pretty reasonably priced. Centrifugal pumps operate in a dry location close to the pond. They’re suitable for larger ponds and are easier and less expensive to maintain, but you can definitely hear them. When you’re selecting your pump size, you’ll need to know the volume of your pond. Generally, if you host fish, you want to circulate all the water in your pond at least once every hour. So if you have a 1500 gallon pond, you want a pump rated for 1500 GPH (gallons per hour) or more. As always, there are other considerations, depending on the design of your pond and any water features. A pond professional at your local shop can help you walk through your options.
