I have an irrigation well that is rust staining a white vinyl fencing that surrounds my yard.....a recent sample returned these results:

Hardness 84.0 mg/l
Iron 0.23 mg/l
Manganese 0.084 mg/l
pH 7.8
Chloride 9.3 mg/l
Sodium <20.0 mg/l
Nitrates <0.5 mg/l

I am wondering what might be the best way to correct this. I need to maintain a 12GPM flow rate when the system is running.....I have approximately 1 acre of lawn and on hot days will use 2500 gallons per day keeping the blue grass irrigated.

Any ideas ?