Drain and refill is the only safe fix for high stabilizer.

You can’t safely lower cyanuric acid without partially draining your pool. No chemical trick, no magic filter, no shortcut that won’t cause more problems.

CYA doesn’t break down naturally. It doesn’t evaporate. It barely degrades from sunlight. The only reliable method is dilution — drain some water, add fresh water. How much? Depends on your target level. Aim for 30–50 ppm. If you’re at 120, you need to replace about 60–70% of the water to get back in range. Test after refill to confirm.

There are products that claim to “remove” stabilizer. They don’t work well. Most are just oxidizers that mess with your chlorine balance or leave sediment. Don’t waste money. Even pool stores will tell you to drain and refill if they’re honest.

If you’re worried about water waste or local restrictions, check if partial draining is allowed. Some areas let you drain to a certain level for pool maintenance. Pump the excess to a sanitary sewer (not storm drain) to avoid runoff issues.

High CYA means chlorine is less effective. That’s the real problem. You can temporarily “sh