Can liquid chorine be old when you buy it?

[twesterd]

I have a 10,000-13,000 Gal pool. I bought Bravo/HEB brand concentrated bleach from HEB in Pflugerville, TX. The bottle says its concentration is 8.25%. It is hard to interpret but I think it says it was manufactured Feb of 2014. It is now Aug 2014. I have numerous test kits: one is a Leslie's brand complete pro-care DPD test kit. I am sure it is a re-branded Taylor kit, but sure what the exact equivalent is.

My issue: I add a gallons of chlorine and the level gets to around 1 ppm free chlorine and it is barely at the bottom of the scale for the Leslie test kit. I also have another kit that came with the house that uses 5 drops of reagent to turn the water yellow. That test seems more sensitive at the lower end of the scale. It also confirms the level is around 1 ppm. I can't really measure total chlorine because added the 3rd reagent, the color is so close to the free chlorine level (near bottom of scale) that I have no confidence. It does get a little pinker/redder, but not by much.

It really appears to me that the chlorine is nowhere near 8.25% as listed on the bottle. I added 4 gallons on Wednesday, 5 more on Thursday, and 3 more today and cannot get the ppm of FC to 2 or more.

NOTE: The pool is crystal clear, the water looks great and there is no cloudiness or algae.

I did measure PH and it was originally high at 8.0. I added muriatic acid and it lowered to 7.6. The PH seems stable. The total alkalinity is 70 ppm. I have a gunite pool and the water in this area is hard with lots of calcium. I have 500-550 ppm for calcium and, again, no cloudiness. The CYA is around 80-90 ppm.

Do you agree that the bleach seems unusually weak? Has anyone else heard of bleach being so weak when it is "brand new" (used within days of purchase)?

 

[jblizzle]

Welcome to TFP!!!

The bleach certainly could be old and if it was stored in the sun or heat, the strength will drop even quicker.
What is the code on the bleach that you got?

FYI, I highly recommend you add the crucial FAS-DPD Chlorine Test to your kit as it takes the guess work out of the chlorine numbers. It is also required if you ever get algae and need to SLAM the pool.

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

 

[twesterd]

The code on the bleach is 14 211 16:16 B1 TX-01

 

[jblizzle]

The 211 is actually a Julian date (day of the year) ... So it was from July 30. Certainly not old.

I do not think it is a bleach problem so much as that you must have something in your pool consuming the FC very quickly.
If you had the FAS-DPD test you could report the FC and the CC.
I think the ShockLevelAndMAINTAIN Process is in your future.

 

[twesterd]

I'm not sure what would be consuming the chlorine. I made my comment because I was using Chlorox without issue. Adding a gallon would normally be a lot for the pool. On top of that, the Bravo chlorine, when smelled directly from the bottle, did not have a strong chlorine smell. I will get the Taylor FAS-DPD test kit now and report back the results.

 

[duraleigh]

I'm not sure what would be consuming the chlorine.

Two things consume chlorine in a pool.......sunlight and organics that the chlorine is having to kill. That's it.....two things.

wait 'til evening (eliminating sunlight) and measure your FC several hours apart. If your FC drops between those readings, you are left with the inescapable conclusion you have organics (usually algae) in your pool. By far, that's the most common reason for your FC to Drop.

 

[twesterd]

I also have over 100 degree weather too. I am in Texas

FYI: No pool store in the area carries the FAS-DPD test kit. I tried four different stores. So, I have to order online. The water is clear. There is nothing visible in the water on the walls. I will try adding another brand until the kit arrives. I also ordered a 25 pound bucket of Lithium Hypochlorite: seems to have all desirable features except price.

 

[jblizzle]

Not surprising. That is why I gave you a link to where to order it. That lithium is very expensive and not worth the cost when bleach is so much cheaper and more readily available.