The title of your post hints that you think it is water that controls whether beer is malty or not. It isn't. It's malt. It is true that the chloride ion in the water (of which you have quite a bit) smooths, sweetens, mellows, rounds the beer and increases mouthfeel (all things one might associate with malty flavors/qualities) and sulfate tends to render bitterness harsh, rough, assertive and dry (things one might associate with hops) but if the malty flavors aren't there to be enhanced, they won't be.
If you want beers that are not malty then use small quantities of malt and use mostly base malts that is, avoid the highly flavorful colored malts. Mash at a low saccharification temperature (144 °F or thereabouts) in order to produce a highly fermentable wort.
Brew with neutral water i.e. RO water with about half a tsp of calcium chloride in each 5 gallons. When the beer is finished taste it and taste it again with various amounts of calcium chloride and/or calcium sulfate added in the glass. This will show you what chloride and sulfate ions do to beer flavors. Tweak future recipes according to what these tastings indicate to you.