Where we mention this product

• 

  essentials

  Hardness Test Kits and Strips: What to Buy

  Most accurate · Best for: Industry-standard drop-count titration — ±0.5 gpg accuracy for borderline cases and professional use

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  water

  Water Hardness Explained (gpg, ppm, How to Test)

  Pro accuracy · Best for: Drop-count titration for precise gpg when sizing a softener