Using a lot of bleach for SLAM

Jayzeem83

Member
Feb 17, 2019
22
Austin, Texas
Hi all, I’ve begun tackling my green pool today. I cleaned out the filter and began slamming this morning. I’ve been testing every 30 minutes and each time my free chlorine is at 1ppm. I am adding well over a bottle of 121oz 8.25% bleach every 30 minutes and I’ve already gone through 10 bottles. Each time I test the free chlorine it is at 1ppm. My other results are below.
CYA: 25
Ph: 7.5
FC: 1

Is this normal? Thanks.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
7,835
Northern NJ
Yup, keep at it. A green pool can take a lot of chlorine to kill all the algae.

How fresh is the chlorine? You check date codes on the bottles?
 

kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
40,389
Tallahassee, FL
That is a good date. It means it was made on the 30th day of 2019.
The more you test and dose the pool to try to get and KEEP the FC at SLAM level the faster your SLAM will go. Every time your FC gets below the SLAM level you give a bit of advantage to the algae. You are in a war and every addition of FC will push the algae back more.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Looks like the same bleach I use from HEB. Some things I would add to help all of us guide you better:
1 - Update your signature with your pool details. Your pool size is important as well
2 - A CYA of under 30 is questionable as the readings aren't accurate below 30. You might consider verifying once again and/or adding just enough stabilizer to be sure the dot disappears at 30 (SLAM of 12). If you overshoot slightly to a CYA of 40, then increase the FC to 16. Just use Poolmath as best as you can.
3 - Make sure you increase the FC to the SLAM level (i.e. 12) and maintain it in the beginning. It should never drop to 1. By then all your effort (and bleach) is history and you're starting all over. Add bleach and check the FC about 10-15 minutes later and maintain it.
4 - Can you give us an idea why the green so early when the water is still probably chilly (unless you heat)? Just so we have an idea of how it got to this point.
5 - Have you added anything else to the water recently other than bleach or perhaps acid?
6 - Next time you post your results, please post the FC, CC, and CYA.
7 - How old is your pool (if you know)?
8 - You might consider lowering the pH to about 7.2 before spiking and maintaining that FC at 12.

Oh, and welcome to TFP! :wave:
 
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kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
40,389
Tallahassee, FL
Here is what I want you to do. Use Pool Math to see how much chlorine you will need to get your FC up to SLAM level. Add that amount of chlorine, making sure your pump is on as it should be 24/7 during the SLAM. Now let the pump run for about 15 mins then retest to see where the FC is. Let us know what happens.
 

Jayzeem83

Member
Feb 17, 2019
22
Austin, Texas
Thank you for all those pointers. Wish I had posted before I began as I feel what I did today is a waste of money. I’ll update answers to all your questions shortly.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
7,835
Northern NJ
Do what Kim asked and test your FC 10 to 15 minutes after adding. You want to see your FC is at shock levels as soon as it mixes. The chlorine can get used in 30 minutes with strong algae.
 

Jayzeem83

Member
Feb 17, 2019
22
Austin, Texas
4 - Can you give us an idea why the green so early when the water is still probably chilly (unless you heat)? Just so we have an idea of how it got to this point.
The green is from lack of maintenance. No heat.

5 - Have you added anything else to the water recently other than bleach or perhaps acid?
I added yesterday muriatic acid to balance ph.

6 - Next time you post your results, please post the FC, CC, and CYA.
FC: 0.6
CC: 2.8
CYA: Using the K2006, I added the solution to the small tube to the full level and could still see the black dot.

7 - How old is your pool (if you know)?
3-4 years old.

Thanks all. I think I need to get my ducks in a row (as you generous folks have outlined) starting this SLAM process again.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
That's a healthy elevated CC level which tells us a LOT of stuff is transitioning from chlorine. What you need to do now is stock up on more bleach and be ready. Get comfortable near the pool, increase the FC to 12, and test again in about 10 minutes. Increase the FC if needed to maintain "12" and keep doing this (every 10-15 min) until the pool begins to hold. It will, but it may take a few cycles of quick testing and bleach additions before it holds. Once it does, follow the SLAM page to the letter and you'll get back on track. Good luck!
 
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kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
40,389
Tallahassee, FL
See if you can get your hands on stronger chlorine tomorrow. Some pool stores have 11%. It might be cheaper in the end if you don't have to burn too much gas to get to it.

You CC is telling us you are in for a battle. Do as Pat says and fight back often and strong! Once you get the the cc to break things will be easier.
 

Jayzeem83

Member
Feb 17, 2019
22
Austin, Texas
Great, thank you all. I won’t have time this week to try again but next weekend I’ll tackle it.

So to clarify:
Should I leave CYA alone despite it likely being really low?
Drop ph to 7.2?
Add bleach to shock level and test after 10 minutes?

Thank you! On a side note, my wife called a pool store and they said they can rectify the green pool for $350. Does anyone have an idea of what they would do?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
21,250
Laughlin, NV
Probably add more ammonia. Do not let a pool store person near this.

You will need more than a weekend to complete a SLAM.

No CYA until you get FC to hold. Watch your pH as it may spike higher with ammonia in the water.