The GEM System will arrive pre-calibrated and ready to activate (less dismantling is required for packing and shipping). Head pressures developed by pumps and piping restrictions on site could require a second calibration of the GEM System mixing chambers and should be anticipated. This process usually takes less than a day to “re-tune” the GEM System to the specific flow altering influences on site. This operation can be accomplished with tap water or wastewater typically fed to the system during normal operation. Water for testing should be free of debris and should be representative of the stream that is normally directed to the system