The primary reason why the VorTech is such low maintenance is because in a typical impeller pump you have a very small gap between the rotating magnet assembly and the inner walls of the powerhead. This gap must be free of calcium or else the powerhead will bind and become damaged.
The VorTech is a totally different design in which there is only one primary bearing surface. The rotating driveshaft is butted directly against this bearing surface and is constantly rubbing against it, thus no opportunity for any calcium to grow. We have selected materials that will take this abuse. Pumps that are shipping from our factory now feature components that will last for the life of most people's usage with no replacement.
I hope I kept this purely explanatory and non-commercial.
I personally am not happy with my Tunze. I purchased the 6000 Turbelle and the 7091 single controller with the magnet holder. For 365. clams I was really hoping for more flow. I understand that it is awider range of flow rahter than a pinpoint as with powerheads but like I said, I am very disppointed with the power.
