About WaterByTheBook – Our Editorial Process

WaterByTheBook is the honest field guide to home water filtration.
We tell you which filter actually fits, what it is certified to remove, and whether
it is worth the money — by the book: from manufacturer spec sheets, NSF/ANSI
certification listings, and the EPA’s own monitoring data. Never from a sales page.

Who writes this

Every guide is written under the editorial byline Thomas Kwayne —
a pen name for the site’s editorial process, not a fabricated expert. No invented
credentials, no stock-photo author. What we claim is exactly what we do: research
against primary sources, stated plainly.

Our process

  • Primary sources only for numbers. Filter certifications are checked
    against the NSF, IAPMO, and WQA listing databases — we distinguish
    NSF-LISTED (verifiable in the database) from manufacturer-claimed,
    every time. Water-quality figures come from the EPA’s public UCMR5 and SDWIS data,
    with the data vintage stated.
  • Occurrence, never verdict. When we report monitoring data, systems
    “reported above a limit” — that is not a compliance ruling and not a health
    verdict, and system-level data is not a claim about your tap. For your specific
    utility, use the Water Watchdog lookup.
  • No medical advice. We report what the EPA limit is and what systems
    reported. We do not tell anyone their water is safe or unsafe.
  • Honest trade-offs, named out loud. Reverse osmosis wastes water to
    drain. Aftermarket filters are cheaper but check the certification. A softener will
    not fix heavy iron alone. Confirm your model before you buy — always.
  • Reproducible data work. Our national studies are computed by
    committed scripts over public-domain EPA data. The method and caveats are published
    with every study.

How this site makes money

As an affiliate, WaterByTheBook may earn from qualifying purchases — it costs
you nothing and never changes which filter we say fits. See the
affiliate disclosure.

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