What is the best air pump for a Koi pond?

Air pumps depend on the volume and depth. There are basically three types of pumps. Large lake type air pumps - this is probably not right for what you are asking. Then there are two types left Linear Diaphragm and Piston pumps, I think you get more mileage from piston type pump like a Medo airpump MedoUSA. read more

The air pump is one of the pond water features essential to Koi Pond maintenance. Adequate aeration is needed for pond organisms to survive and function well. The pond pumps also provide air to the water and it enable pond organisms to get Oxygen and avoid the stagnation of water. read more

Best Pond Air Pump and Best Pond Aerator 2018 (Reviews) Pond aerators are a popular method of providing extra dissolved oxygen and increased water flow to your garden pond water. If you don’t have a natural aerator to provide oxygen, such as a waterfall, or just want extra aeration for your fish, purchasing a dedicated pond air pump system is a great way to oxygenate your water. read more

Second, this added air can also support beneficial bacteria so if one has algae or water quality issues, adding air may improve things. And finally, aerators are often used in the winter to control ice coverage on a pond. read more