This pump threatens a revolution in the pond pumps market. Using the weatherproof electronic controller it allows you to change the flow rate up or down. This has a number of benefits: Pump can be run \'low\' at winter - ticking over at just 15 watts. Adds an extra degree of excitement to watercourses and waterfalls. Flow can be increased in the summer - bringing additional oxygen to your fish when they need it. Important: The pump can only be ran dry on or below the water level.