Episode 2: The 7.5% Rule. The Most Important Number You've Never Heard Of | The Pools Scientific Podcast
The Pools Scientific PodcastShow Notes
Your test strip shows chlorine. The water looks clear. But is your chlorine actually working? In this episode, chemical and nuclear engineer John Cooper breaks down the relationship between cyanuric acid (CYA) and free chlorine — and the single ratio that determines whether your sanitizer is doing its job. It's called the 7.5% Rule, and most pool owners have never heard of it. John covers what CYA is, why it belongs in your pool, how it quietly blunts your chlorine's effectiveness as it accum...
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