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Essential GuideTest First

Well Water Testing Guide: Test First, Buy Second

You can't choose the right treatment system without knowing what's in your water. Here's how to test your well water properly.

The rule this entire site is built on

Test your water before buying any treatment system

We say this on every page because it matters that much. The right iron filter for 3 PPM iron is wrong for 10 PPM iron. The right softener setting for 15 GPG is wrong for 30 GPG. A $30–$80 water test saves you from buying the wrong system.

What to test for

Hardness (GPG)Determines softener sizing and settings
Iron (PPM)Ferrous and ferric — determines iron filter need and capacity
Manganese (PPM)Often accompanies iron, treated similarly
pHLow pH damages equipment; below 6.5 needs acid neutralizer
Hydrogen sulfideMust be field-tested — dissipates in mail-in samples
Coliform bacteriaAnnual testing recommended for private wells
E. coliMore serious than total coliform — requires immediate action
NitratesCommon in agricultural areas, health risk at high levels
ArsenicOdorless and tasteless — only detectable by testing
TDS (total dissolved solids)General water quality indicator

Testing options by method

Test strips ($10–$20)

Good for: quick hardness and pH screening. Not good for: iron type, bacteria, arsenic, nitrates. Use as a starting point.

At-home test kit ($20–$50)

Good for: hardness, iron, pH, basic bacteria indicator. More accurate than strips. Some kits include a wide panel of tests.

Mail-in lab test ($30–$400)

The most accurate option for most parameters. Use a certified lab — SimpleLab's Tap Score is the one we recommend most for well water owners because their well water panels are designed specifically for the contaminants we care about (iron speciation, sulfur indicators, hardness, bacteria, arsenic, nitrates, and more). Order the panel that matches your concerns.

Recommended Tap Score panels for well water
Tap Score uses EPA-certified labs and provides specific treatment recommendations based on your results — not generic "your water has X" reports. The panels below cover the most common well water concerns:
Essential Test →Advanced Test →Extended Test →
Read our full Tap Score review →
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On-site professional test

Most accurate for hydrogen sulfide (which dissipates before mail-in samples arrive). A water treatment professional or your county health department can test on-site.

How often to test

After you get results — what to do

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