[nexxo]

Originally Posted by starbuck3733t

Anyway , check out the specs on the swissflow SF800: http://www.swissflow.com/html/800_5.htm

so no paddle or moving parts - all done optically. I wish I knew how the hell they did it.

As Arrivaldo states, it does have one moving part --a simple impellor-- which interrupts the IR light beam when spinning. The impellor is suspended in the chamber in such a manner that, when there is flow, it floats in the liquid and spins in place. The inside of the chamber has channeling fins causing a small vortex in the liquid, that keeps the impellor centred right in the middle of the chamber. As such while spinning there is no physical contact between the impellor and the chamber, so no friction and no wear or tear.