Directions for start-up (Empty Tank, system off):
1) Add FilterBalls to tank. They are soft and can be pressed down when filling.
2) Replace Multiport Valve or tank lid and rinse the new media for 2 minutes, then backwash for 2 minutes.
3) Set to filter mode.
4) Backwash again when pressure increases by 10-15 PSI.
More info at: http://www.filterballs.com/