Why Does Soft Water Test Hard?

Decoding the Complexity of Hard Water

Water is essential for life, and its quality directly impacts our well-being. As we delve deeper into the realm of water quality, the term "hard water" often surfaces. But what exactly is hard water? Let's unpack its definition, origins, effects, and treatments.

Hard Water Defined

To understand hard water, we must turn to the authoritative voice of the Water Quality Association (WQA). Established as the gold standard for water treatment insights, the WQA provides clarity on numerous water-related topics.

From the WQA's perspective:

"Hard water is a common quality of water which contains dissolved compounds of calcium and magnesium and, sometimes, other divalent and trivalent metallic elements."

The term "hardness" historically described waters that were challenging to wash in, highlighting the soap-wasting properties of such water. It prevents soap from lathering efficiently, causing an insoluble precipitate in water. This characteristic of hard water often leads to scaling in cooking pans and pipework.

However, what really matters for consumers is understanding how hard water behaves. The WQA further explains hard water in terms of untreated mineral concentrations. Their degree of hardness standard outlines how hard water's behavior changes with varying concentrations. But a noteworthy challenge arises here: the standard can be confusing when equated with a "hardness test" results, as it doesn't always reflect the water's behavior. It ignores water can be softened by changing mineral behavior eliminating the requirement to remove the mineral to make soft water.

Here is a hardness test explainer video. Learn what a hardness test tells us, doesn't tell us and when to use one.

Origins of Hard Water

What causes this hardness? Calcium and magnesium, the primary agents of hard water, are abundantly found combined with other elements in the earth's crust. Common forms include chalk, limestone, and marble.

Addressing Hard Water: Treatment Methods

From the WQA's desk:

"Softening hard water can mitigate many of its objectionable effects."

Water can be softened via:

1. Chemical softening: This involves lime and lime-soda softening and polyphosphate softening. Polyphosphate softening can soften water without removing the minerals therefore a hardness test which indicates mineral concentration is not a suitable test to determine whether the water will behave soft.
2. Membrane separation softening: Employing Nano filtration.
3. Cation exchange softening: Using inorganic, carbonaceous, or organic base exchangers.

Currently, the most predominant method for home-based water softening is cation exchange or salt-based softeners. However, there's a notable evolution in this realm. As of 2019, advances in polyphosphate softening are reshaping the industry. Yet, a concern arises here: the WQA and its affiliates appear slow in recognizing the differences between mineral concentrations and water behavior.

To further this, the American Water Works Association (AWWA) has clarified that "polyphosphates are water softeners." There's a pressing need for updates, especially when the chemical softening realm is advancing, with polyphosphates taking a front seat.

In Summary: The Hard Facts About Hard Water

• Hard water isn't just about mineral concentrations; it's about water behavior.
• A hard water test indicates the concentration of hardness minerals, it does not indicate how the minerals will behave.
• The WQA's insights, though valuable, need updates in light of new water treatment methodologies.
• Understanding hard water's effects and treatments can lead to informed choices, benefiting both health and household maintenance.

Remember, as we navigate the complexities of hard water, staying informed is our best tool. Whether it's through salt-based softeners or new-age polyphosphates, the aim remains clear: ensuring water quality for all.