CYA levels

[poolwilly]

Hi! I've read a number of threads on CYA in TFP-- so helpful. This website is amazing.

I think I am doing things right, but just want confirmation, as last year I messed up (I'm a newbie). I made the mistake of using (probably poor quality) test strips last year, added too much CYA and then got chlorine lock.

This year I am using the Taylor kit, and it feel so much more reliable. But when I opened my pool, CYA was essentially undetectable. This would be possible after 8 months of being closed for the winter, no? With dilution by rainwater, etc? Now I have the pump running and put Trichlor tabs in. (We are going to add a SWG later, but we are waiting to make some piping fixes, so I figured I can get my CYA from the tabs). I want to SLAM, but should wait until the CYA is 30, right? And this will take a while, right? From other posts, it seems like each puck will raise the CYA in my pool approx 1ppm. So I have to wait for 30 pucks to dissolve? Since opening, 10 have dissolved, and CYA remains undetectable (I'm testing daily).

Thanks for your help. I was so bummed to have added too much CYA last time, that I want to be extra careful.

 

[bobloblaw42]

Are your K-2006 reagents unexpired and have you repeated the CYA test with a sample that has come up to room temperature?

Can you post a full set of test results from your kit and a description of the pool (or pics) that make you want to SLAM?

FC
CC
pH
TA
CH
CYA

 

[Rancho Cost-a-Lotta]

Welcome Willie!

Trichlor tablets are not the preferred way to raise cya levels. They're very acidic, and can cause damage to pool surfaces and equipment. As you found, they are also slow to dissolve. You should be looking for 100% cyanuric acid, unusually sold as chlorine stabilizer.

Please post a full set of test results. Additionally, please complete to your signature.

Create Your Signature - Further Reading

www.troublefreepool.com

 

[wireform]

Have you tested the water? What are your numbers as you may not need to slam unless the water isn't clear. For now you need granular CYA hang in a tube sock over the edge of the pool in front of an active return to get it into the water quickly. Add 30 CYA as per poolmath for your pool then use liquid chlorine to slam. When you've met all 3 criteria you can go back to tabs but you'll need to watch the CYA as it'll climb fast and get you in trouble.

 

[poolwilly]

Thank you all! Really helpful. I was worried about the test kit so made a long trek out to a pool store and had my numbers checked. Looks like the Taylor was just fine and CYA was indeed low. Really helpful to hear thoughts on tabs for raising CYA. I've slammed now and it looks great. (Though I am looking at a plumbing question, but I'll post that elsewhere.)
Thank you! And I added more to my signature-- thanks for the suggestion.

 

[Griswald]

FYI...chlorine lock does not exist. Adding more chlorine will always work, but it can get expensive and difficult to maintain that high a level of chlorine.