The guys over at NordicHardware do a great review of the Zalman Reserator 1.  What is it you ask? 

"It is simply a 60 cm high, cylindrical, hollow tower made of blue anodized aluminium. At the bottom of the reserator you find the water pump that circulates the water in the system. The pump has a maximum flow at 300 l/h and according to the specifications it needs about 5 W."