Do I add CYA before or during SLAM process?

[HeyAandA]

Hey all, I'm trying to bring a neglected pool at a new (to me) house up to par. The test strip (waiting on my full testing kit to arrive) shows no FC and no CYA and I'm a little confused about the process to correct the CYA.

I know I need to get my CYA up to 30-50, but do I need to do that before adding chlorine or can/should I do it at the same time? I don't want to waste chemicals/money if I shouldn't be adding chlorine until the CYA level is appropriate since the chlorine burns off quickly without the CYA.

If I'm understanding correctly, it seems like it's supposed to be a balancing act and that I should be adding chlorine and upping the CYA at the same time until levels are maintained. But I'm not sure if that's right.

Thanks!

 

[Butterfly]

Welcome to the forum

If I'm understanding correctly, it seems like it's supposed to be a balancing act and that I should be adding chlorine and upping the CYA at the same time until levels are maintained. But I'm not sure if that's right.

Yep, right. (but the SLAM process is not done until you pass all three tests. See red lines in my sig)

Could you get confirmation on the zero CYA before you start the SLAM process?

To answer your question, (assuming zero CYA) if you are adding granular CYA, add about 30ppm via sock method hanging in front of a return. Until the CYA is gone from the sock, use FC 10 as your shock level.

Once gone from sock, use 12 as shock level.

 

[HeyAandA]

Thanks, Butterfly!

I'm going to have the water tested by the pool store since I don't have my full kit yet. That should confirm the zero CYA level.

I appreciate your help!

 

[jblizzle]

Welcome to TFP!!!

I don't think a pool store test will confirm anything ... and CYA happens to be the test they are the worst at. You would think they could ID that you have 0 CYA ... and yet we have seen posts where people have taken in tap water (definitely 0 CYA) and been told that they do have CYA in the water.

 

[HeyAandA]

I just checked and my testing kit is supposed to arrive today so hopefully I'll be able to test on my own.

Welcome to TFP!!!

I don't think a pool store test will confirm anything ... and CYA happens to be the test they are the worst at. You would think they could ID that you have 0 CYA ... and yet we have seen posts where people have taken in tap water (definitely 0 CYA) and been told that they do have CYA in the water.

 

[Butterfly]

btw, you can start the SLAM process using 10 FC as shock level. If you are unable to read the CYA test later today (depending on when the kit arrives) you can SLAM assuming zero CYA.

All FC added after the sun is off the pool will work on nasties in the pool and no FC will be lost to sunlight.