The Spanish Association of Koi (AEK), an association that brings together fans of ornamental fish from Japan, shows how they have adapted our water tank for its use as a pond.
To develop the low head recirculating aquaculture system, they have used a coarrugated, galvanized steel sheet water tank (diameter=4,56 m, volume= 18000 liters).
The base (concrete mixed with Sika polypropylene fibers) was waterproofed with SIKA 107 Top Seal and acrylic paint for swimmingpools.
The water circulation and filtration run exclusively through two airlifts of 110 mm. They aim to create a circular current whose direction of rotation can be easily changed just moving the airlift’s elbows. A Secoh 41 watts air pump provides air to the airlifts via 20 mm flex PVC pipe. A third, external airlift will purge the dirt from the central drain. It will be powered by a second and smaller air pump coupled to a timer.
The result can be seen in this video, shared by Diego Jordano, Head of Ecology at the University of Sciences in Cordoba.