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CYA / Stabilizer Calculator

Calculate how much cyanuric acid (stabilizer) to add to protect your chlorine from the sun.

CYA / Stabilizer Adjustment

Don't know? Calculate it here
0 if new pool or recently drained
Recommended: 30-50 ppm for regular pools

Stabilizer (CYA) Dosage

Amount to Add -- oz
Also equals -- lbs
Will raise CYA to -- ppm
Buy Pool Stabilizer on Amazon
How to Add Stabilizer:
  1. Put stabilizer in a sock or pantyhose
  2. Hang in front of a return jet OR place in skimmer basket
  3. Squeeze periodically to help dissolve
  4. Takes 3-7 days to fully dissolve and show on test

What is CYA (Cyanuric Acid)?

CYA (also called stabilizer or conditioner) protects your chlorine from being destroyed by UV sunlight. Without CYA, you can lose 90% of your chlorine in just 2 hours of direct sunlight!

Target CYA Levels

Pool Type Target CYA
Regular Chlorine Pool30-50 ppm
Salt Water Generator (SWG)70-80 ppm
Indoor Pool0-20 ppm (optional)
Warning - CYA is Permanent!
CYA doesn't break down or evaporate. The only way to lower it is to drain and refill with fresh water. Don't use stabilized chlorine (trichlor pucks) if your CYA is already high.

CYA Too High?

High CYA reduces chlorine effectiveness. If your CYA is above 100 ppm, your chlorine is nearly useless!

How CYA Gets Too High

How to Lower CYA