The Cation Analysis: Sodium, Potassium, Ammonium, Magnesium, and Calcium
 
Ammonium is the form of nitrogen released from decay of organic matter.
Detection in drinking water may indicate contamination with sewage or fertilizaer
 
Sodium and potassium are essential minerals, but excess can indicate salty water.
Excess sodium can cause hypertension and other health problems. Most water
softeners add sodium to your water, and if sodium is already high, it may push
your water into the danger zone. Some softeners use potassium instead, which is
generally considered harmless
 
Magnesium and calcium are essential minerals and add flavor to water, but
excess can cause “hard water,” and scale or mineral deposits in plumbing.
 
Strontium is common in seawater, and is occasionally found in ground water. It
has properties very similar to calcium.
 
The cations can also affect how your water will react during household tasks like
washing, laundry, cooking and home brewing.
What to do about it?
 
If magnesium and calcium are high (and the water is very hard) a water softener
can remove these, at the cost of adding more sodium or potassium. If sodium or
TDS are also high, a reverse osmosis system may be required.