Affiliate disclosure

There are currently no affiliate links on this site.

In the future, we may join affiliate or referral programs, for example from companies that sell water test kits or water-treatment equipment. If we do:

• Pages with affiliate links will say so near the top, before the first link.
• We may earn a commission if you buy through one of those links, at no extra cost to you.
• Commissions won't change what our pages say about test results, health limits, or legal requirements. Those always come from the cited government or university sources.
• We'll keep pointing you to free or low-cost options, such as testing programs run by health departments, wherever they exist.

This page will be updated with the names of any programs we join.