You can grab a basic TDS meter for under $15 online. They’re cheaper than a pizza dinner and last forever. Seriously, I’ve had mine for years, and it still works after being dropped in the sink twice.
Just don’t buy the super fancy Bluetooth ones. You don’t need an app to tell you the number. Your eyeballs work fine. Unless you’re a water scientist in a lab, the $12 version is perfect.
A few warnings (because I’m your water-savvy friend)
Don’t drop it in hot coffee or a fish tank by accident. The meter will cry. Also, make sure to store it dry—moisture is its kryptonite.
And please, for the love of hydration, calibrate it every few months. A little packet of calibration solution costs pocket change. Otherwise, your meter might lie to you, and then where will you be? Drinking lies, that’s where.
