Pond air pump for Koi and large ponds. Available in three different sizes with an output ranging from 20 to 60 litres of air per minute at low energy consumption. The rugged construction of the air pump ensures that the pump produces little noise and has a long lifespan. In this Koi-flow aeration set 6 air stones are included and a 50m air hose. The air-stones allow you to add air in several different places in the pond and filter thereby optimising oxygen levels.