Choosing the correct koi pond water pump is essential to keeping your koi pond clean and clear. Your pond pump must operate 24 hours a day - 7 days a week in order to maintain the health of a pond, filter system, and most importantly, the koi fish themselves.
Your pond pump should circulate the entire volume of your pond in approximately half an hour.
There are two basic types of water pond pumps available; external and submersible. The size of your pond will determine its pond pump needs.
To figure the size of a rectangle or square koi pond simply calculate: Length x Width x Depth x 7.5 = Gallons. For round or circular ponds you should calculate: Diameter x Diameter x Depth x 5.9 = Gallons. Figuring the correct size of your pond is very important. You can also use our Pond Volume Calculator.
External Koi pond pumps are typically used for medium to larger sized ponds. Typically, 1200 gal or more would be sufficient for an external pump. When dealing with larger ponds, an external pump is usually the best choice.
External Koi pond pumps can generate heavy flow rates needed to work with biological filters that require weekly backwashing. Another advantage to an external pump is the ease of pump maintenance. Due to the large amount of organic material that is generated by your pond, pond pump impellers can easily clog. Larger external pumps often come with leaf baskets and traps that make cleaning your pump trap while keeping your hands dry.
Submersible water pond pumps are often better suited for smaller ponds; 1500 gal or less.
Submersible water pond pumps are situated underwater. This type of pond pump is often more economical, easier to install, more energy efficient, and operated with very little to almost no noise. Since it is submerged, it can be a bit troublesome to clean and is typically more visible.