Mike Callahan
Plumbing & Installation Contributor
- 28 years residential plumbing experience
11
Articles published
H2O Insider
Publication
About
Mike has installed more water treatment systems than most people have reviewed. He contributes installation guidance, evaluates ease-of-install scores, and calls out any product that requires a professional where it claims DIY. He is based in Oakland, CA.
Review & Editorial Standards
All H2O Insider reviews follow our editorial standards and review method. We buy and use every filter we review, and check each certification claim against the listings. Affiliate relationships never influence our recommendations.