Bob Lowry Why High Cyanuric Acid Makes Chlorine Weak

Your pool can test “fine” on chlorine and still struggle to stay clear, safe, and algae-free. The missing piece is often cyanuric acid (CYA), the stabilizer that protects chlorine from UV sunlight but also controls how much chlorine is actually active at any moment. When CYA climbs too high, the kill speed drops, problems linger longer, and the fix is rarely just “add more chlorine.” We walk through what cyanuric acid is, why the pool industry embraced it, and the chemistry most people...