Chlorine Lock- Uggghhh

[DadaBug]

I hate chlorine locks!
34,000gal vinyl liner inground pool
Pools open 1 week - water is crystal clear, no algae, no debris
I keep adding chlorine and nothing....these are my levels:

Free Chlorine .35 (insanely low)
Total Chlorine 6.5
pH 7.2
Alkalinity 125
Calcium Hardness 12
CYA 44
Phosphates 2500 (insanely high)

Ok, I know my Phosphates are WAY HIGH. Just not sure what I should address first. I don't want to keep dumping chlorine especially with the high prices & shortages these days. I even drained a little water (definitely not enough to make a difference) just 34k is ALOT of water. Can anyone give me some guidance?

Thanks!

 

[Shirker]

I hate chlorine locks

Well, you are going to love what you are about to discover here!

 

[Newdude]

Hey Dada and 7 years later, welcome to posting !!

So here’s the deal. Chlorine lock is a made up pool store thing to explain why your sky high CYA buffers tons and tons of your chlorine. Usually after a year or two after using pucks and/or powdered shock. With a CYA of 44, (always rounded up to the next 10, so 50), you should have no problems keeping FC.

Unless

1) bogus pool store test
2) even worse test strip guess
3) last years chlorine degraded
4) last years test strips are even less accurate
5) you have the start of an algae bloom which I doubt you caught in time without reliable testing.

How are you testing and what chlorine are you using ?

 

[Shirker]

Chlorine Lock is not really a thing. You need to do an OCLT (Overnight Chlorine Loss Test). This will tell you how much chlorine you are losing overnight which ideally should be almost none. The sun will degrade chlorine during the day. But at night, if you lose chlorine, it is because you have organics (probably algae). I assume those are pool store numbers? They look very precise but probably are not very accurate. You will need your own reliable test kit to do an OCLT.

Overnight Chlorine Loss Test
Test Kits Compared

 

[BassPlayingDude]

It is also possible there is ammonia in your water ..

 

[Newdude]

It is also possible there is ammonia in your water

The CYA generally drops, possibly to 0 with ammonia. If OP is holding at 50, it’s *probably* a good thing.

 

[Shirker]

Free Chlorine .35 (insanely low)
Total Chlorine 6.5

I'm very skeptical of these numbers. What does your pool smell like?

 

[DadaBug]

Yes, I am ashamed to say I use the test strips, normally- but my levels are always perfect so I haven't bought a true test kit. However, the results I posted were from the pool store, which I had tested 2 separate days (and they were pretty much the same). We had very little sun, so I don't think any chems are getting eaten up by the sun- and i normally put in bleach and baking soda to maintain my levels (stopped going to the pool store years ago when I found this website!)

I'm thinking of SLAM again......not sure?

 

[Shirker]

Great, then that means you know the basics. Time to get a real test kit and get your water properly balanced.

 

[Newdude]

I'm thinking of SLAM again......not sure?

You simply can’t SLAM without your own test kit to test at will and many times a day / late in the day

normally- but my levels are always perfect so I haven't bought a true test kit. However, the results I posted were from the pool store, which I had tested 2 separate days (and they were pretty much the same)

here is the *other* thing. Strips and pool stores have given you a false sense of things being ‘perfect’. Ignorance is bliss.

 

[mknauss]

As you have been around the forum for 7 years, you know we rely on accurate test results from a proper test kit. So order one now.

While you are waiting on your test kit, add 5 ppm FC worth of liquid chlorine / plain bleach to your pool each evening with the pump running. This will replenish the FC lost each day to the sun and also inhibit any algae in the water from growing further.

 

[DadaBug]

Pool does not smell and looks great- I am so confused! especially since my CYA is on target

 

[JoeSelf]

You'll need a test kit to SLAM properly Test Kits Compared SLAM Process Recommended Levels

 

[skimmerswimmer]

Pool does not smell and looks great- I am so confused! especially since my CYA is on target

If you don't have your own proper test kit, you can't assert that your CYA or any other readings are correct. We don't trust pool store results and they won't help during a SLAM anyway. Get the proper kit, take your measurements, and hopefully any issues or questions you have can be addressed here.

 

[DadaBug]

Ordering my test kit now.....and staying clear of the pool store!!!!

 

[DadaBug]

As you have been around the forum for 7 years, you know we rely on accurate test results from a proper test kit. So order one now.

While you are waiting on your test kit, add 5 ppm FC worth of liquid chlorine / plain bleach to your pool each evening with the pump running. This will replenish the FC lost each day to the sun and also inhibit any algae in the water from growing further.

Thank you

 

[skimmerswimmer]

Don't forget the speed stir.
(you can thank me later).

 

[HeyEng]

Don't forget the speed stir.
(you can thank me later).

No doubt. Second favorite accessory. First is the robot.

 

[DadaBug]

I FINALLY got my Taylor Test kit today! K-2006
My readings:
FC 1ppm
CC 1ppm
pH 7.0
Alkalinity 140
CYA 95
Calcium 50

Any suggestions on what I should tackle first to get this pool to hold&read Chlorine? I have Bleach 7% avail chlorine or Shock Dichlor 55% available, not sure what I should use

 

[skimmerswimmer]

CYA looks high. Maybe half drain & refill, then add chlorine to meet the respective FC/CYA ratio. Cal Hypo will raise your CH a little which doesn't really matter too much with a liner pool. Either should be fine.