My first SLAM. Having a hard time maintaining shock levels. Is this normal?

[Tastybread]

Hey everyone. Got my test kit and found that despite Leslie's guidance, I did in fact have chlorine in my pool and that they were full of it. My pool was still cloudy and my free chlorine levels were very low so I decided to try SLAM'ing for the first time.

For my 16000 gallon pool I added 480oz of 10% liquid chlorine to reach a shock level of 24 FC. Waited an hour and it brought my FC level from .2 to 1.7. I added 460oz of chlorine and waited another hour to find my FC levels reach 9. I just added 300 more oz but I'm worried. Is this normal? My back yard has empty gallon jugs scattered everywhere and I'm worried that I might just be wasting money.

This is what I got the last time I tested:
FC 9
CC 2
PH 7.5
CYA 60

i appreciate any insight you guys can give me. Thanks.

 

[Beens]

First thought, are you sure your chlorine is fresh? If it's not fresh it could be a much lower % than you think it is which would take a lot more chlorine to raise the FC.

 

[pooldv]

Yes, test about 15 minutes after you add to validate your numbers. Number of gallons could be off, percentage or something. Are you targeting 24?

Please add your pool info to your sig as shown here, Pool School - Getting Started

 

[Swampwoman]

Welcome, Tasty. From your earlier thread, I understand you've been having trouble getting chlorine to hold.
After you've confirmed the freshness of your bleach, could you do a second quick test and report back?

When you add your bleach to get to 24 ppm, test a half hour later and tell us what percentage/how many ppms are left.

If its less than half, sometimes its necessary to oxidize stuff by doing an aggressive start of repeated, close additions to break down things in the water that might be fighting the chlorine. This is rare, but worth a quick check.

Regardless, in any slam, the beginning requires a lot of repeated additions to get chlorine to start holding and take the upper hand over the organics It is normal to need to dose every few hours at the start, but will normally taper off over time.

It might not hurt in this case to give us a bit of "event history" of your pool along with the specs you add to your signature. Eg. When did you discovered it wasn't holding FC, when did you open it, was it left uncovered if you close for winter, stuff like that. It might help us help you have the most efficient slam possible

 

[Tastybread]

Hey everyone, sorry for not replying. So I woke up this morning and did another test and found that over night my FC levels held ok. Tested and showed that FC was 6.5 and CC was .5. So I added 3 gallons of chlorine, waited an hour and just tested to find my FC levels at 28. I think I finally broke the Algea fever! CC levels seemed non existant; not sure if that's a bad thing.

So after spending more time on the forums last night I think I realized something. My pool was never green when I started this, but it was extremely cloudy. I always just thought that was a harmless side effect and Leslie's sold me a ton of Clarifier to solve the problem but it never did anything. I'm realizing now that that just meant I still had algea in the pool. So all the chlorine I was adding last night was probably going to that. Woke up this morning and while not completely clear, it was looking much much better. I'll keep updating as the day goes on, but things are looking pretty good I think. This site is really amazing. I link should be given to everyone as soon as they install a pool.

 

[kimkats]

That morning testing is awesome! Good job!

When do we get to see it???????
Kim

 

[Pool Tool]

CC = 0 is a good thing. Think of CC as spent FC that no longer does you any good. CC's are formed as a result of FC working to eradicate something. Be happy at 0 to 0.5 ppm CC. Nice job.

 

[Patrick_B]

Sounding good! Let us know how it progresses. Sounds like you dodged a bullet pretty well there.

 

[Tastybread]

So five hours later after my last post I tested again and found that I went from an FC of 24 down to 17. I added another gallon of liquid chlorine. Also, I don't know if it matters but I live in Mesa AZ where it's been well over 100 every day lately and I'm sure the temperature of my pool is around the 80's. How much will that impact my chlorine levels? I was also wondering how much chlorine do you add after a swim session and what do you guys do when you leave the house for a couple of days? I assume you raise the chlorine to shock levels?

Thanks for the support everyone. Here is a picture of my pool. Not perfectly clear but considerably better than it was before.

 

[kimkats]

There are two ways to take care of the pool while you are gone.

-Overnight-raise FC to SLAM

-more than 3 nights-Raise FC to SLAM and put in a couple/few pucks. JUST know what your CYA is and what it will be when you get back and take the pucks out.

Yes temps do affect your FC use. Higher temp=use more FC, how temp=less FC used.

Kim