I like using a radiator cap with a
zinc sacrificial anode. racewayparts.com product number Z17700 16 lbs. cap for $34.55. What sold me was the first time, I took off the cap and saw all the salts and dissolved anode. I use nothing but distilled water and
antifreeze but remember all the different metals in your system can cause an electrical charge in your coolent even with a grounded system.
Bill K