This is a speciality filter - In this instance to raise PH and deal with ammonia in water and raise PH.

Please Note:
When installing Turbidex Systems or Turbidex Media, it is necessary to allow the media to stand in the vessel which has been filled with water for the following times. The Turbidex should not be put into service or backwashed until this priming time has elapsed

16in Vessels and smaller - 30 mins
18-30in Vessels - 60 mins
36-48in Vessels - 120mins
Larger than above - £180mins