A clearer understanding of water.

When chlorine (or chloramine) reacts with natural organic matter in source water, it forms hundreds of DBPs, primarily trihalomethanes (THMs, e.g., chloroform) and haloacetic acids (HAAs). Hundreds of additional DBPs exist and are not currently regulated at the federal level.

An apple cider vinegar (ACV) rinse is a reasonable periodic add-on when you wash hair in very hard water. It is not a substitute for a water softener or a true chelating shampoo. The useful effects come from acidity, not from any special “vinegar magic.”

The most common driver of accelerated anode consumption is elevated electrical conductivity in the water, not the mere presence of sodium ions (or the absence of Calcium). I have been solving corrosion problems for three decades, from residential systems in Utah to mission-critical industrial and institutional systems on multiple continents. The corrosion-mechanism is not mysterious once you understand what is happening at the electrode interface inside your water heater.

Ion exchange trades calcium and magnesium for sodium (or potassium) on an equivalent basis. The resin does not know or care whether the water started at 5 or 55 grains per gallon. It swaps one equivalent of hardness for one equivalent of sodium each time. The average is about 7.5 milligrams per liter of sodium added for every grain per gallon of hardness removed.