Water treatment services

The single most important thing to understand is that softening and filtering are not the same job. A water softener is designed to reduce hardness minerals — calcium and magnesium. It is not a purifier. A carbon filter improves taste and odor and reduces chlorine. A reverse osmosis unit is the one that goes after dissolved solids and a long list of chemical contaminants. Buying the wrong one is the most common and most expensive mistake in this category, and it usually happens because the person selling was only selling one thing.

Certification is the honest way to compare claims. NSF/ANSI 42 covers aesthetic effects — chlorine, taste, odor, particulate. NSF/ANSI 53 covers health-related contaminant reduction and carries over 50 specific claims including lead and VOCs. NSF/ANSI 58 covers reverse osmosis systems. NSF/ANSI 44 covers residential cation exchange softeners. NSF/ANSI 55 covers UV microbiological systems. A product is certified for specific claims, not "certified" in general. Ask which standard and which claim, in writing.

Start with a test, not a salesperson. If you are on a public system, your utility must send you a Consumer Confidence Report every year by July 1, and the EPA hosts a search tool to find it. If you are on a private well, the EPA recommends annual testing for total coliform bacteria, nitrates, total dissolved solids and pH through a state-certified lab, and your local health department may test at no cost. That data tells you what equipment you actually need before anyone quotes you.

Be skeptical of the free in-home water test. It is a legitimate diagnostic in some hands and a sales script in others, especially when the person performing it also sells the equipment. If a sale is made in your home for more than $25, the FTC Cooling-Off Rule generally gives you three business days to cancel and requires the seller to disclose that right. If nobody mentions the cancellation right, that tells you something about the company.

How to choose

Get an independent water test first

A lab you hire has no equipment to sell you. For a public supply, read your Consumer Confidence Report before spending anything. For a well, use a state-certified lab.

Ask which NSF/ANSI standard and which claim

"NSF certified" alone is close to meaningless. NSF/ANSI 53 for lead is a specific, verifiable claim. Get the model number and look it up yourself.

Match the equipment to the test result

Hardness means a softener. Chlorine taste means carbon. Dissolved solids and specific chemical contaminants point to reverse osmosis. Bacteria in a well points to UV plus fixing the well. One box does not do all four.

Separate the drinking water problem from the plumbing problem

Scale that wrecks water heaters is a whole-house issue. Water you don't like to drink is often a single under-sink unit. Point-of-use systems installed under a sink run $170–$580 for unit and labor, far less than treating the whole house.

Never sign during the demo

The soap-suds and precipitate demonstrations used in in-home sales are chemistry parlor tricks, not diagnostics. Take the quote, get the lab test, get a second bid.