
Test strips are generally only relatively accurate. I have compared this brand to another and they differ a little, especially in terms of ph, kh or gh. Compared to the liquid tests, none agreed. So why are they good. I use them when I'm repairing water systems, say after a big water change or after using chemicals. During the correction, I need to know that I'm doing better, not worse. If the bands are near normal, I use liquid tests for more accurate readings.

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