cyanuric acid ?

[CV3720]

I've read a couple posts that mention cyanuric acid (CYA). The test strips I purchased for my new tub are "6-in-1", but don't check that. Is it an issue, and at what level?

[bud16415]

They may call it stabilizer on the 6in1 strips.

CYA slows down the action of the chlorine. A little is good too much is bad.

It is added to the chlorine you are using dichlor as it is used in pools and sunlight removes it.
In a tub it doesn't see much sunlight so the CYA builds.

I use dichlor until it reaches 50ppm and then switch to household bleach. When the CYA drops to 30ppm i switch back. 

[Tman122]

Some people who use dichlor never check it and don't care. It makes the chlorine less effective (add more)

[A.O.]

They may call it stabilizer on the 6in1 strips.

CYA slows down the action of the chlorine. A little is good too much is bad.

It is added to the chlorine you are using dichlor as it is used in pools and sunlight removes it.
In a tub it doesn't see much sunlight so the CYA builds.

I use dichlor until it reaches 50ppm and then switch to household bleach. When the CYA drops to 30ppm i switch back.

The CYA will drop back down?? I thought that once it was there it was there for good..

[Tman122]

I should of been more clear. The PH will go down (because of the higher acidity) So they adjust PH and change water every 3-4 months.

[bud16415]

It will lower with adding water for splash and steaming away. Sunlight will also lower it I’m told.

I also do a small drain and refill sometimes mid winter to stretch the water life. Draining 50 gallons out of a 350 gallon tub and refilling only takes a few minutes and really improves your numbers. 

[bud16415]

Also a warning if you switch between dichlor and bleach, get pool bleach or use regular household bleach but get the plain old bleach not the stuff that has smells in it or the splashless stuff as it will cause foam. 

[A.O.]

Go over here and do some looking around, good info and people there also..

https://www.troublefreepool.com/blog/pool-school/