Move Up to 47,000 Litres Per Hour With a Powerful External Pump

The Aquascape Ext 12000 is a single-phase external pond pump rated at 12,500 GPH (47,319 LPH) at zero head, delivering the high flow required by large koi ponds, waterfalls, and stream features that exceed the practical capacity of submersible pump designs. As a non-submersible external unit, it is installed outside the water and requires primed plumbing connections, enabling easier maintenance access compared to pumps installed on the pond floor.

High Flow, High Efficiency External Pumping for Large Ponds

External pumps at this output level are more energy-efficient per litre-per-hour than submersible pumps of similar capacity because the motor is air-cooled rather than water-cooled and benefits from larger motor frame sizes. The oil-free, TEFC-enclosed motor runs on standard 115V or 230V single-phase power with no field wiring changes required, and the fan cooling extends motor life in warm operating environments. The 3/4 HP motor provides a maximum head of 6.4 m (21 ft), suitable for tall waterfall and high-head stream installations.

How to Use

Mount the pump on a level concrete pad or platform adjacent to the pond, below the water surface level to assist self-priming. Connect the 7.6 cm (3 in) inlet to the pond through a valved bulkhead fitting or suction pipe. Connect the 5 cm (2 in) discharge to the waterfall or filter system plumbing. Prime the pump with water before first start-up. Plug into a GFCI-protected outdoor outlet and verify normal flow at the waterfall or discharge point. Service the mechanical seal annually per the included maintenance guide.

Ideal for large koi ponds above 15,000 litres (4,000 gal), professional pondless waterfall installations, and large water garden features requiring reliable high-volume circulation at heads up to 6.4 m (21 ft).