Water not holding chlorine level

Jul 13, 2014
20
Memphis/MI
I just opened my pool 12 days ago. After correcting what the pool store called a chlorine lock problem (TC 8ppm FC 0) I now have an issue with my water not holding FC level. Over the past four days I’ve added 16 gallons of chlorine (12.5%) along with 12 bags of regular shock and my TC & FC levels have not changed still 0 & 0. The pool water is relatively clear but not sparkling. At that point I went to the internet and began searching for answers. That’s when I came across this forum. The following are my latest test results from my pool store.

FC-.5ppm; TC-.5ppm; CC-0ppm; pH-7.5; Hardness-140ppm; Alkalinity-130ppm; Cyanuric Acid-4ppm; Copper-0ppm; Iron-0ppm; Borate-3ppm.

Their recommendation; 13#s Calcium Hardness, 5#s Stabilizer & 3 bags of Shock.
 
:wave: Welcome to TFP!!!

Chlorine lock is a buzz word that pools stores use that is meaningless.

How are you getting test results?
You need to ultimately follow the ShockLevelAndMAINTAIN Process to eradicate whatever is in the water and to do that you need one of the Recommended Test Kits that has the FAS-DPD chlorine test.

Do not start adding more stabilizer and "shock" {whatever that is} to the pool until you have reliable test results.

Please add your pool details to your signature and as described HERE as it will help us help you in the future.

If you have a vinyl pool, then adding calcium is a waste of money.

Check out Pool School, starting with these:
ABCs of Water Chemistry
Recommended Pool Chemicals
How to Chlorinate Your Pool
 
After correcting what the pool store called a chlorine lock problem (TC 8ppm FC 0) I now have an issue with my water not holding FC level.
Might I ask what their "cure" was for "chlorine lock".


I've ordered a TF-100 test kit but I'm assuming it will take at least 3-5 days before I receive it.
Great, it will be a great feeling for you to know what is really going on in the water,


Anything I can do in the mean time?
Read Pool School (link above and on every page). Ask questions if you don't understand something.

You can add 1-2 bottles of bleach every evening to try to maintain some chlorine ... maybe. Beyond that, wait for the test kit :goodjob:
^^^ What Jason said!!
 
Welcome to the forum :wave: we can help.

"Over the past four days I’ve added 16 gallons of chlorine (12.5%) along with 12 bags of regular shock and my TC & FC levels have not changed still 0 & 0."
You have to remember if you add chlorine you have raised the FC & TC levels. In your case the pool is just using and or loosing it faster than you are putting it in.

You just opened it. Is it new to you or have you had it a few years ??

Reading as much as you can in Pool School is a very good thing till your kit arrives. http://www.troublefreepool.com/content/
That and brush the pool daily. Keeps algae from getting a grip just in case you're low on FC.

You posted a CYA or "stabilizer" reading of 4ppm and it's likely you should be around 30-50. If you really are at 4 that can be the reason your FC is going poof !! CYA protects the chlorine from the sun. Without it the sun will eat chlorine faster than you can pour it in on a nice sunny day :sunny:

Can you please add your pools info as outlined here -> http://www.troublefreepool.com/content/165-getting-started
 
That just means there was something in your pool consuming the chlorine ... nothing was locking anything up.

Might have been an ammonia problem which will require a LOT of chlorine. There are no mysteries ... chlorine is consumed by 2 things: 1. the sun or 2. organics in the water

Most pool store employees do not understand the chemistry, so they resort to buzz words and non-sense.
 

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So no CYA and high CC ... that has seemed to point to ammonia quite often this year.
Add 10ppm of FC and test it again in 30 minutes and report back the FC and CC.

Eventually you will need to follow the ShockLevelAndMAINTAIN Process and should likely add about 30ppm of CYA once that is started, but lets see what the above test shows.

You forgot the pH test.
 
I would keep targeting 10ppm and testing every 30 minutes until you start to get a higher FC reading. Then you are going to want to add some CYA and follow the SLAM.

You could take a sample to a pet store and have them run an ammonia test on it to confirm.
 
I added a 2nd 2 1/2 gallons of chlorine 1 hour ago and check the reading twice 30 minutes apart and the FC increased from 1.0 to 3.0 and the CC increased from 2.0 to 2.5 and seems to be holding. Based on your earlier note does this mean I should add some CYA now? If so how much do you recommend, my CYA reading is currently 0 what is my shock FC I should be shooting for to SLAM since the chlorine/CYA chart starts at 20 CYA?
 
No. I would want to see a FC up higher before you add CYA. Since the CC keep rising (this should be zero), I think you need to keep adding bleach to eliminate the ammonia before adding CYA.

On second thought, go ahead and get some CYA dissolving, but keep dosing to 10ppm and testing every 30-60 minutes if you can to try to get that ammonia gone.
 

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