A suitable water pump is a vital component of any fish pond, and especially important when it comes to keeping prized koi carp healthy and happy. These innocuous-looking pumps serve a number of purposes, including pushing water through filters to remove harmful detritus and aerating the water to allow your koi carp to breathe, grow and thrive.
As you can imagine, then, choosing the right pump for a koi carp pond can be a more complex process than finding a pump suitable for a simple ornamental pond, and choosing the wrong pump can leave your koi unhealthy and unhappy. When you are shopping around for a new carp pond pump, make sure to ask yourself the following questions before you hand over your hard-earned cash.
How much pumping power do you need?
The first and most important step to take before buying a new pump is to work out how much water your koi pond holds at full capacity. As a general rule, your new pump should be powerful enough to pump the entire amount of water in your pond within two hours; for example, a 1000 litre koi pond should be serves by a pump powerful enough to achieve flow rates of at least 500 gallons per hour.
This can become a prohibitively expensive prospect, however, if you have a particularly large koi pond, or a pond large enough to house other fish and aquatic creatures as well as your koi. In these circumstances, a slower flow rate may still be suitable as long as you supplement the pumps water aeration abilities with other forms of water aeration. Aquatic plants that aerate water (such as water hyssop) are particularly useful here.
Should you choose a surface or submersible pump?
You will also have to choose whether to opt for a surface or submersible pump. While these pump types serve the same essential purpose, they are quite different in form and function and are suitable for different types of koi pond:
- Surface pumps are placed by the edge of your pond, or can be submerged in your pond as long as they are contained within a watertight dry chamber. They are well-suited to large koi ponds containing many fish, as they tend to have excellent power ratings and flow rates. They are also easier to access, which makes maintenance easier and less messy. However, surface pumps are also louder and less energy-efficient than submersible pumps, and will require some form of protection from storms and other inclement weather.
- Submersible pumps are submerged beneath the surface of your pond as their name would suggest. They tend to have less pumping power than surface pumps, but they also use less energy since they don't have to pump water up to ground level. They also require no manual priming, and are hidden from view to give your koi pond a more natural look.