The Alistep float-operated flush is based on the principle of self-priming siphons and has the main advantage of completely emptying the first-stage tank, removing the need for any pre-treatment (degreasing tank) and special screening conditions (screen size less than 40 mm, pebble trap, etc.). Furthermore, it requires no power supply.
The float tank is emptied by gravity via the central tube ; this is a measure of the reliability of the link between tanks. Also, emptying has been carefully designed to minimise its height in relation to other existing systems, hence a reduced need for a change in levels between the raw water intake and the filters.
To prevent sludge deposits and blockages in the system, the lateral emptying arms on the Alistep raw water emptying mechanism ensure that the tank empties completely.
The system is low maintenance requiring only that the system is rinsed with clean water once a month.
Since the first-stage tank is emptied completely, the system is low maintenance : the siphon and tank require rinsing with clean water once a month.