Chlorine Too Low

[dpdeleon]

Hi,
I can use a little help with figuring my chlorine problem out.

When I first opened my pool 5 gallons of liquid chlorine (hypochlorite) was used. When the water cleared I added 24 oz of powdered shock and noted that 2 days later I didn't have a CL reading. I added about 64 oz of shock and things began to look better. My Cyanuric before all this was 0. I kept adding powdered shock in small amounts and things were looking good. Water was and still is perfectly clear. The shock raised my Cyanuric to 37 so I began adding liquid pool chlorine of the 10% CL variety. After adding (over a week) about 4.5 gallons of liquid pool chlorine I couldn't get a reading (using Taylor test kit). I added 2 gals of liquid CL and waited 4 hours. Took it to the pool store for a reading and my CL is at 0.1 after adding 2 gals of liquid CL the same morning as the reading.

The liquid chlorine is from last season. Does CL go bad if unopened and left to the elements in the Northeast? What else could be the cause of the low readings? The CYA looks good.

Any help is appreciated. Thanks

 

[duraleigh]

It sure sounds like you need to SLAM.......what does your water look like?

 

[Texas Splash]

The liquid chlorine is from last season. Does CL go bad if unopened and left to the elements in the Northeast?

Yes it does. See below.

Chlorine Date Code Decoder - Further Reading

www.troublefreepool.com

 

[HermanTX]

You show to have the K-2006 test kit, so trust that. Post a full set of test results fron your own testing.
Appears you have algae. You can also do a Overnight Chlorine Loss Test test which will indicate if you need to do a SLAM.

Chlorine will degrade over time. Heat is even worse but both affect the strength. Suggest you buy new LC.

 

[dpdeleon]

It sure sounds like you need to SLAM.......what does your water look like?

Pool water is perfectly clear.

 

[an1vrsy]

I added 24 oz of powdered shock and noted that 2 days later I didn't have a CL reading.

I added 2 gals of liquid CL and waited 4 hours.

What will work better for you is to add chlorine, then allow time to mix, 30 minutes then test to see how much it raised or not. Waiting 2 days or 4 hours will not give you accurate information. You have a good test kit, your results with that kit you can trust.

 

[Ssouthar]

I would also be careful where you get your liquid chlorine from. When we first moved to our new home and inherited the pool, I was buying it from the corner grocery store until I discovered they were not replacing it and had very old supply. I noted that Home Depot was storing theirs out in the sun so that was a no go. Finally started going to a trusted pool supply store that was a further drive but after questioning them, they assured me they took in daily shipments on pallets that got sold quickly to local pool maintenance folk. Anyway, I buy from them now and do check the dates and so far so good. I keep mind at the most for 1 month - go through a case in about that time frame. Brad mentioned the website for learning date codes for various producers. Good info!