What Causes Purple Stain in a Swimming Pool and How To Fix That?
What Causes Purple Stain in a Swimming Pool and How To Fix That?
Why do I have purple Stains on My Pool Surfaces?
Purple stains or Copper Cyanurate is caused when the CYA (Cyanuric Acid) aka chlorine stabilizer or pool conditioner levels are very high in the pool and then it reacts with any copper that may present in the swimming pool water.
Purple Cyanurate is a swimming pool water chemical imbalance problem and it is NOT an “organism” or algae issue.
It’s most often seen in the spring at pool opening. Although it has been “noticed”, cooler in cooler water which helps this reaction more readily occur.
Purple staining in the swimming pool is further made worse by the following water imbalance issues:
- High pH level in the pool – over 7.8ppm
- High Total Alkalinity – over 150 ppm
- High Cyanuric Acid level – over 100 ppm.
- Copper – over 0.5 ppm.
How Do I Get Rid of Purple Stains in My Pool?
Now when you know what caused the purple stains, it’s time to fix the issue. To fix that issue you should balance the swimming pool water and lower CYA levels in it. You can partially drain the pool or use Swimming Pool Water CYA Reducer. Once the cyanuric levels are within normal ranges, and the water is in balance, the purple dust will dissolve back into the water.
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