I have a closed loop GSHP that was installed in 2014 and have become concerned recently that the water used to mix with glycol and fill the ground loop, may have been taken directly from our well instead of using distilled water as quoted at the time of installation. The water in the ground loop has been tested recently and my suspicion has been confirmed. The water was found to be very hard at 384 mg/L CaCO3. I am concerned about scaling in the heat exchanger and reduced efficiency and/or damage to the system. I am curious to hear if others have had this issue and what the recommendations are to address this concern. Thank you.