I've been using distilled water + salt additions for my last few brews. I am going to order a Ward labs report so I can use my tap water. How do you account for the additions that a campden tablet contributes to the water profile?
All hailing frequencies are now open whereby to channel @RPh_Guy. A few years ago he was writing a peer reviewed paper on this general subject. If anyone can help here, my money rides on him.
To be sure, add Campden Tablets made from potassium metabisulfite instead of sodium metabisulfite to your beer at a rate of one tablet per 20 gallons of water.