Direct answer: Water System Guide publishes its research with the same evidence rules it applies to products: every coverage figure below is a count of published records, not an estimate. Research coverage describes what Water System Guide has studied and published. Search-engine indexing is a separate question — which of those URLs search engines choose to crawl and show — and it is controlled by the search engines, not by Water System Guide.
What research coverage means
Coverage figures on this page are computed from the same sources that drive the site: the brand index, the model-page registry, the research corpus, and the live provider directory. A figure here means a record exists and has passed the relevant review gate. It does not mean a product is recommended, a claim is certified, or a URL is ranked in any search engine.
National research library
- 16 published brand profiles, documenting 141 named configurations across brand research.
- 340 model-page decisions in the public registry — 33 exact-model evidence pages and 307 manufacturer-catalog reference pages.
- 71 research pages across treatment families, system comparisons, guides, decision tools and trust standards.
- 353 committed source files across 27 immutable capture manifests; published pages cite 157 unique source records.
Treatment-family research
Research is organized around 4 primary treatment families — ion-exchange water softening, whole-house water filtration, reverse osmosis, and well-water treatment — plus 2 separate decision axes: salt-free conditioning and point-of-use placement. Each family and axis has a dedicated page under treatment families, for 6 dedicated system pages. Salt-free conditioning is an alternative scale-control mechanism, not hardness removal; point-of-use is a placement axis, not a single mechanism.
Model-page research
Model pages publish in two evidence tiers:
- Exact-model evidence pages (33) — backed by an approved evidence snapshot; exact-model claims, certifications, and rated conditions are checked against the record.
- Manufacturer-catalog reference pages (307) — bounded to facts documented in the manufacturer catalog, such as product identity and family scope; performance, certification, price, availability, and serviceability remain unknown where unverified.
In total, 33 model pages are backed by approved evidence snapshots. A category or brand name never proves a reduction claim; verify the exact model, standard, named substance and rated conditions.
Guides, comparisons, and decision tools
Guides cover selection, testing, cost frameworks and ownership. Comparisons use 8 consistent decision dimensions — problem addressed, mechanism, testing required, point of treatment, installation, maintenance, limitations, and ownership cost. Decision tools publish their formulas and keep unknown states unknown.
Local provider directory research
The installation-professionals directory contains 122 published provider profiles across 1 active market(s) (Greater Houston at present). Profiles are source-checked, listed alphabetically, and never ranked; payment does not change verification. New markets publish only after local evidence and provider gates pass.
What is not yet covered
Scheduled brands are listed on the brands hub with no profile claims implied. Catalog-reference model pages await exact-model evidence before they can carry exact-model claims. Cost guides do not invent national averages. Where evidence is absent, the page says so rather than estimating.
Research coverage vs search-engine indexing
Research coverage and search-engine indexing are different things.
- Research coverage is what Water System Guide has studied and published as records: the library, registry, and directory counts on this page.
- Search-engine indexing is whether Google or another engine chooses to crawl and show a URL in its results. Indexing is decided by the search engine.
Water System Guide publishes its discovery surfaces — sitemap and the machine-readable library index — for engines to use. At the latest crawl, the live sitemap contained 536 URLs, including 340 model pages and 122 provider profiles. Publication of a research record does not guarantee indexing, and indexing does not change the evidence rules attached to the record.
How this page is verified
Coverage figures derive from the named sources above and are recomputed as the library changes. This page carries an effective and review date per the editorial policy; material changes are recorded. Questions about evidence and corrections follow the methodology and the correction process described in the editorial policy. Learn more about Water System Guide.