What filter should I use for water quality testing?
The short answer: it depends on the test—glass microfiber for prefiltration/clarification, a membrane at the method-specified pore size for microbiological analysis, and PFAS-free products if PFAS is part of the panel.
Quick answer
Water quality testing typically involves more than one filtration step: a coarse prefilter (glass microfiber) to clarify a particulate-heavy sample, then a method-specific membrane for microbiological or chemical analysis. If PFAS testing is part of the panel, every piece of equipment—including filters—needs to be PFAS-free.
Follow the method, not a generic default
Environmental and water testing methods are often prescriptive about exact filter specifications—this isn't a category where guessing is a safe substitute for the specified method.
See our full environmental and water testing filtration guide.
Need a more specific recommendation?
Tell us your exact sample and instrument, and we'll confirm the right spec.