O.k. finally got around to filling it, hooking up the pump, cleaning the filter, etc. Had the water tested and here are the stats:

Total hardness: 100ppm
pH: 6.0
Combined Chlorine: 0
Free Chlorine: 0
Total Alkalinity: 0
Cyanuric acid: 0

water volume: 5300 gallons

Filter type: Clearwater Cartridge filter (75 square ft filter.)

Filter was removed and soaked in a cleaning solution (very green )

Water now is still green and all leaves have been removed.