Chlorine level

[Barry J]

Ok, so shock it tonight to bring Cl level up, that is what I thought...should I worry about Cyanuride level going up ??
Would 90 appear to be a good level for stabilization

[FormerBromineUser]

The pucks have given you a lot of CYA. 90 is very high. Your shock level is 20-22ppm FC. http://www.poolsolutions.com/gd/best...e-chart.html#a

Use bleach or liquid chlorine rather than bagged shock as that will not raise your CYA level.

Have you considered doing a partial drain and refill of the pool to lower your CYA?

[Barry J]

To be honest with you, I have not used the pucks that often this year, maybe twice a week, if that...I will use the liquid shock tonight, think I should switch to the granular HTH, I have some of that left ??
With a week of 90 degree weather and sun all week, think that will lower my CYA ?

[FormerBromineUser]

Your CYA will only lower significantly through dilution and occasionally over the winter.

What is in the HTH granular? Is there cyanuric acid? Does it say Tri-Chlor or Di-Chlor? Both of those will raise your CYA higher.

[Barry J]

I am going to shock it tonight..The liuquid shock I have is Sodium hypochlorite 12.5%...will this raise my CYA level, or can I use it

[FormerBromineUser]

That is perfect! That is liquid chlorine with NO CYA. Remember, you need to get the FC up to about 22ppm and keep it there by testing and adding until you pass the overnight test.

[JimK]

That is perfect! That is liquid chlorine with NO CYA. Remember, you need to get the FC up to about 22ppm and keep it there by testing and adding until you pass the overnight test.

Agreed.

Keep in mind I'm no expert, just a forum member who's been here awhile. Unfortunately the "experts" that use to post here haven't posted in a long time.

It's important to keep FC at shock level until 3 criteria are met;

1. Water is clear; no visible algae
2. < .5 CC (combined chloramines)
3. Overnight FC loss is 1ppm or less.

As was stated, do not use anything that contains CYA, i.e. pucks, sticks, DiChlor, trichlor, etc. stick with plain bleach (no scents, no splashless varieties) or "liquid chlorine". Bleach and liquid chlorine (they are the same thing actually, just perhaps different concentrations) do not add CYA.

Do consider a partial drain/refill to lower CYA. 90 is pretty high, requiring more FC to perform a proper shock. Unless you are using a SWCG, your CYA should probably be 30-50ppm.

I hope this helps.