Where we mention this product

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  essentials

  Hardness Test Kits and Strips: What to Buy

  Budget pick · Best for: Cheapest option at $5.97 — dual-pad design lets you verify each reading; 50 strips, fine for a one-time test

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  problems

  Hard Water Stains in the Toilet (Clean + Fix the Cause)

  Best value test · Best for: Two-pad design that separates low (0–25 gpg) and high (25–250 gpg) ranges — fewer false reads if your water is on the harder end of the scale.