Does anything else raise CYA except dichlor?

[watson524]

8/9/15 we added Dichlor to get our CYA level up since it had been about a month. Tested after a pump cycle and CYA was 37 (right between 35 and 40 on the tube). Today we did our weekly testing and I thought ok let me test it for giggles. We've only used 8.25% bleach since. It's at 50 and honestly, it's likely more like 53 or 54. I couldn't believe what I was seeing.

There wouldn't be anything else that would raise that right? And oddly, we added about an inch of water right before testing today so I'd have thought that would lower it since I was "diluting" the water.

 

[jblizzle]

Only dichlor, trichlor (which can be pucks, or sticks, or granules), or stabilizer (cyanuric acid) add CYA to the water.

If you did the tests in different lighting, that could affect the results.

 

[Isaac-1]

Also if you use powdered CYA stabilizer it can take up to a week to register on the test.

 

[chem geek]

Even if we can't figure out why you saw a rise, 50 ppm is not a problem. Just keeping using bleach after each soak. Eventually the CYA should drop at around 5 ppm per month due to chlorine slowly oxidizing it.

 

[watson524]

Tests read in the same light (kitchen counter) and same time of day (so same sunlight coming in through the windows). Interesting about powdered stabilizer (which I assume is what I have since it's in the dichlor granules) but I also have kept a running total of dichlor added and the 37 CYA was about right for the amount of dichlor.

Guess I'll call it a mystery and use the bleach accordingly for the next 2 months or so and test the CYA once / month to see where things are at.