Add CYA before or after shocking?

bryanw9

Member
Jun 1, 2011
13
Pittsburgh, Pa
Hello everyone.

I am in the process of opening my pool.

My numbers are as follows:
PH: 7.2
TA: 90
FC: 10
CC: .5
CH: 350
Cya: 10?

I am using the TF-100 kit and the water in the cya tube is all the way to the top and I can barely see the dot. I know I need to add stabilizer and have it ready to go. I am in the process of shocking right now. Should I finish this process and add the stabilizer after I'm done or should I do it now? If I do it now, and since cya levels take a week to show up, at what point are my levels considered changed for the shocking purposes and daily FC levels? (in other words...when do I start using the higher ppm level of chlorine according to the cya/chlorine chart ?)

Thanks in advance.
 

Leebo

Admin
TFP Expert
LifeTime Supporter
Jul 21, 2011
8,691
Eastern Ohio
How much stabilizer have you added at all? If you've added some at all this year, then go with that amount. Example....if you've added 4 pounds, then your new shock level is based on a CYA of 30. It starts working right away, but takes up to a week to show up on a test. If you've truely only got a CYA level of 10, then add stabilizer to get up to about a 30PPM CYA level. If difference in your shock level is only 3PPM, but you'll save a TON in protecting the chlorine from the sun. Keep a close eye on your CH level too however....don't let it get much higher!

What part of Pittsburgh are you located?? Used to work up in Crafton, and am located just south of Steubenville myself. :D
 

bryanw9

Member
Jun 1, 2011
13
Pittsburgh, Pa
I have added zero so far. My CH level was over 1000 last year but I did a 50% drain twice to get it where it is. I was told that it was fine for a vinyl liner pool. I stopped using the junk the pool store was selling that was causing my problems, so hopefully it won't get any higher? I will add 4-5 pounds of CYA and keep shocking. So your saying I need to switch to the higher shock level immediately after adding the stabilizer, correct?

To answer your question, I live in peters township.

Thanks for responding so quickly.
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
42,989
Tucson, AZ
If using solid, after the CYA is dissolved you should go to the higher shock level. But it will be ramping up while it is dissolving. Like Leebo said, the FC shock level is pretty similar and there is no harm in aiming a little high to be on the safe side while the CYA is being added.
 

Leebo

Admin
TFP Expert
LifeTime Supporter
Jul 21, 2011
8,691
Eastern Ohio
The CH level is fine....but don't add much more. You can get cloudy water or scaling even with vinyl linears. Now that you know "shock" can have calcium however, I'm guessing you'll be fine.

After about 24 hours your stabilizer is working, so presume its there.