You can’t taste nitrates, so stop sniffing your tap water. Buy a test strip kit online (they’re like $15 for 50 strips). Dip it, wait 60 seconds, and compare the color to the chart. If it’s dark pink or purple, you’ve got levels above 10 ppm. That’s your cue to act.
Test once in the spring after the first rain, and once in the late summer. Those are peak nitrate times because of fertilizer runoff. Nobody wants a surprise chemistry lesson in their morning oatmeal.