Try downloading the EZ Water Calculator from this forum (you will need MS Excel). Works very well. You can manipulate your levels by salt additions (gypsum and epsom).
BTW, I'm jealous of your water. We have lots of alkalinity and hardness where I'm at, so I need to dilute with 60-80% Reverse Osmosis water from the grocery store (about $1.20/batch). And then add lactic acid to bring the pH down for most of the lighter brews.
Primary #1:Dunkel #2:Empty
Secondary #1: Peach Rhubarb Wine #2: Empty #3: Empty #4: Sparkling Elderflower Wine
Kegged: Piker Liker Porter, Umlaut my Kölsch V
Bottles: Big 50 Barleywine, Framboise Lambic, Red Rye IPA, Dark Belgian Strong, Belgian Golden Strong, Kicked by a Moose Scotch Ale, Apfelwein, Russian Imperial Stout, Carmelite Tripel, Rhubarb Wine, Barolo Wine
On Deck: Irish Red, Surly Bender clone, Spruced Warmer, CDA