Koi air is a reliable way of supplying aeration to ponds and filterskoi air 25it has an output of 25 litres per minute and comes with a 8 outlet chrome manifold and spares kitkoi air 50it has an output of 50 litres per minute and comes with a 12 outlet chrome manifold and spares kitkoi air 65it has an output of 65 litres per minute and comes with a 14 outlet chrome manifold and spares kit