Disclaimer

Researched, not professional advice

HomeWaterCalc publishes calculators and buying guidance compiled from published standards, regulatory limits, manufacturer specifications and the consensus of verified owner reviews. We do not test equipment in person and we never claim to. Nothing here is professional water treatment advice, plumbing advice, medical advice or a substitute for a licensed professional.

We do not diagnose water and we do not certify it

Nothing on this site tells you what is in your water, and nothing here says any product makes water safe to drink. Potability is a laboratory result, not a property of a product. What we do is describe what a contaminant is, what the published standard says about it, and what class of equipment is designed to address it.

Get your water tested

Every calculator and every recommendation on this site is arithmetic on a measured number. On a public supply, your utility is required to publish a Consumer Confidence Report every year at no charge, and you should also test at your own tap for anything that changes inside your own plumbing, which is how lead behaves. On a private well there is no utility, no report and no operator, and only a certified laboratory test tells you what you have.

What is not a do it yourself topic

Bacteria and coliform, nitrate, lead, arsenic, PFAS, uranium and radium are not do it yourself topics. They are invisible, tasteless and odorless, so you get no feedback at all about whether equipment is working. The limits are legal figures rather than preferences, and lead does not even have a maximum contaminant level: it has an action level of 0.015 mg/L, which is a trigger for utility action rather than a safe concentration, and the health goal is zero. No filter pitcher addresses any of them.

For any of these, contact your local health department or a licensed water treatment professional, match equipment to a certified laboratory result, and verify by retesting after installation.

Certifications

A certification covers a specific claim under a specific standard, not the whole unit. Check the certifying body listing for the exact model and the exact claim rather than relying on the word certified, on this site or anywhere else.

Plumbing and electrical work

Installing water treatment equipment involves plumbing, sometimes electrical work, and frequently a drain connection subject to local code. Backflow protection and air gap requirements exist for good reasons. If you are not confident, this is work for a licensed plumber rather than a weekend, and some jurisdictions require a permit.

Accuracy and liability

We work hard to keep published figures correct and we correct errors when they are reported. Standards, regulatory limits and product specifications all change. HomeWaterCalc accepts no liability for decisions made on the basis of information here. The authority is your own test result, the manual for your own equipment, your local code and, where relevant, your local health department.