How we make money

Hydrology University is a reader-supported educational publication about residential water systems and water science. Running an editorial publication costs money. To fund our work, we participate in affiliate programs and accept advertising. This means that when you click certain links on our site and make a purchase (or take another qualifying action), we may receive a commission or referral fee from the retailer or brand.

These commissions come at no additional cost to you. You never pay more because you used our link, and your price is the same as it would be if you went to the retailer directly.

FTC compliance (16 CFR Part 255)

We comply with the U.S. Federal Trade Commission's Guides Concerning the Use of Endorsements and Testimonials in Advertising (16 CFR Part 255). We disclose our material connections — including affiliate, advertising, and sponsorship relationships — clearly and conspicuously. Outbound affiliate and sponsored links are tagged with rel="sponsored" so they are identifiable to you, to search engines, and to the networks we work with.

Programs and partners we may use

We may earn commissions through programs including, but not limited to:

Amazon Associates — As an Amazon Associate we earn from qualifying purchases.
PartnerBoost — Our Waterdrop, WaterH, VIOMI, Purewell (its own store and its Amazon storefront) and DREO picks on the Best Of hub, WaterH bottles on the Accessories page, Purewell picks on our Gravity and Carbon reviews page, and the New listings rail on the Reviews hub use PartnerBoost tracking. A qualifying purchase through any of these links may earn us a commission at no extra cost to you. These links are separate from our Amazon Associates links.
Retailer and brand affiliate programs — direct programs and networks (for example Impact, Rakuten Advertising, or FlexOffers) for water-filtration brands and suppliers.
Marketplace programs — such as Temu's affiliate program for curated marketplace picks.

Editorial standards

Our ratings are never for sale.

No cost to you

You pay the same price whether or not you use our links.

Data-driven picks

We sometimes recommend products with no affiliate program at all.

Our editorial independence

The presence of an affiliate or advertising relationship does not determine whether or how we cover a product. Our recommendations are driven by our research and editorial standards — not by commission rates. We frequently recommend products that earn us nothing when they are genuinely the best option, and we will say plainly when a popular product falls short. For the full picture of how we keep our reviews honest, see our Editorial Policy and review methodology.

Advertising

In addition to affiliate links, some pages display clearly labeled advertisements and sponsor listings. These are always marked as "Advertisement." Advertisers do not receive favorable editorial treatment in exchange for buying placement. To learn about sponsorship opportunities, visit our Advertise With Us page.

Questions

If anything here is unclear, or you'd like to know whether a specific link is an affiliate link, please reach out through our contact page.