Desperately Seeking Help with Ammonia and CYA

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I have put in 32 gallons of 6% bleach since Sunday night, and the ammonia level has not changed, the chlorine seems to go into a black hole--WHAT AM I DOING WRONG?

Pool Water as of 9:00 AM:
Me, using FAS-DPD Test Kit, and DPD deluxe test kit for non-chlorine measurements:
FC – 2
CC – 11.5
pH – 7.2
TA – 120
CH – 260
CYA -50-60 (pretty subjective test, and dependent on lighting--trying to see when the black dot disappears)
Salt - 5,100 according to my SWG
Ammonia (2-part sodium salicylate/sodium hydroxide test) – 8+

Here is what I have done, below. I realize that the first three additions were too small as I didn't enter the gallons of water in my pool to the pool calculator (Doh!), and so it was about half of what I should have added to shoot for 26ppm FC. Did that somehow make the pool water impervious to chlorine? Why is all this chlorine not affecting the CC? All of this was to try and affect the ammonia, and that hasn't budged an iota.

Also, the pH has been dropping, and I thought high chlorine would make the number go up. Do I have a problem there? I have added nothing but 6% bleach since Sunday night (after having dropped the pH to 7.5 w/ muriatic acid.

5/16 5:00 pm FC 1, CC 2.5, pH 7.4 Added 477 oz bleach
5/17 5:45 am FC 5.5, CC 7, pH 7.5 Added 384 oz bleach
5/17 9:45 am FC 6.5, CC 6.5, Added 363 oz bleach
5/17 11:45 am FC 7, CC 8, Added 828 oz bleach
5/17 2:00 pm FC 8, CC 10.5 Added 780 oz bleach
5/17 9:00 pm FC 7.5, CC 9,
5/18 6:00 am FC 3, CC 6.5, Added 1218 oz. bleach (shooting for 28ppm FC)
5/18 9:00 am FC 2, CC 11.5 !?!

As always, grateful for any help/advice. Thanks.
 
Thank you so much for the help.

OK, I put 5 gal. of pool water in a bucket, added 1 oz. of 6% bleach, waited an hour and tested: FC=10.5, CC=22. I then repeated the test using 0.5 oz. 6% bleach in five gal. of fresh pool water, and after an hour tested again: FC=1.0, CC=12.5. What does this tell me? What do I do based on this?
 
In the first cycle, you added 96 ppm of chlorine, and still had a CC level of 22. That means you are going to need something over 100 ppm of chlorine, probably more, to clear up the pool. For your pool, that means something in the neighborhood of 40 gallons of 6% bleach. The actual amount could be higher or lower, because none of the measurements will have been exact, but it should be in that general range.

The fastest way to clear things up would be to go out and buy a whole bunch of chlorine, and then shock the pool in the evening with a target FC level of 28, adding chlorine hourly. If your raise FC to 28 hourly three or four times each evening, you should have things taken care of in two or three days. You can shock during the day, but then you will need more total chlorine to compensate for the losses to sunlight.

This also means that your current ammonia level is over 10, and was presumably much higher when you started. It is very unusual to see the ammonia level that high. That usually only happens when you get fertilizer in the pool.
 
Though one can try and clear this up with oxidizers, such as chlorine, with water this bad one can also do some water replacement (partial drain/refill). Replacing the water might be less expensive than trying to clear this up only with chlorine. At least it's another option I just wanted to throw out there. You can, of course, do both.

The reason you are getting high CC readings is that with the somewhat high CYA level it takes chlorine longer to oxidize the ammonia so it sticks around longer as monochloramine which registers as CC and, by the way, also registers on the ammonia test. 1 ppm of ammonia will register as 5 ppm CC so your CC reading of around 12 ppm would also show up as ammonia of 2.4 ppm even though it's not really ammonia anymore since the ammonia test really reads both ammonia and monochloramine (in ppm N units).

The good news is that with measurable FC you have certainly killed off any bacteria that may have converted some CYA into ammonia in the first place (assuming that's what happened). Since you aren't just seeing the chlorine form CC immediately but rather some seems to be forming it more slowly, this is an indicator of other organics that are slower to oxidize, such as partially broken down CYA that didn't make it all the way to ammonia. This is what I found in my own pool where I needed about twice as much chlorine as would be predicted based on the ammonia level alone.

To avoid this problem in the future, find a way to close your pool such that you never let the chlorine get to zero -- either shock before closing when the water is cold (< 50ºF) and open in the spring before it warms up or add more chlorine during the winter, assuming it doesn't freeze over.
 
JasonLion and Chem Geek,

Thank you for the help. My guess, and that is all that it is, is that the cause of this imbroglio was fertilizer. For the past several years I have used a lawn service, and while the pool is surrounded by concrete of about 6', which is sloped downward away from the coping, some probably made its way into the pool. I have harped on the guys about being careful--but what are you going to do? I can't be there every moment looking over their shoulder.

I am going to do some draining and filling tomorrow, as my salt reading was high to begin with and all this bleach (58 gallons so far!) has driven it up to within 10% of the max.

As for the closing at a water temp of <50F, I'm going to have to cogitate on how to make that work. We have a bevy of lovely mature hardwoods in the yard; oak, maple, ash, and yellow poplar, and they don't seem to worry about the pool water temperature when they decide to shed in the fall. Closing temp. is usually more like 55-60F.

I continue to be profoundly grateful for the help, and BTW, the ammonia reading is coming down. It has left the realm of opaque blackish green and is now ensconced at a lovely Irish Kelly green. One takes solace wherever one finds it!
 
This morning my pH had dropped to 6.8 from 7.2 yesterday morning. I added another 27 gallons of bleach last night in three additions. Would you expect all this bleach to lower the pH by 0.4 in ~24 hrs.? As always, thanks for the help.
 

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Thanks. That is what I thought I knew about chlorine and pH, but I'm darned curious about what could have dropped the pH so precipitously over night. I adjusted with borax as soon as I saw the low pH and got it back to 7.2, but I'm always paranoid about things I don't understand.

Thanks again.
 
Chlorine consumption/usage is acidic so when you add a hypochlorite source of chlorine the pH goes up and when it gets consumed the pH comes back down. When the chlorine is high, however, you can get a falsely high pH reading, but that's not your situation so bringing your pH up a bit is reasonable.
 
I just wanted to put a final finish on this whole sordid imbroglio, and say thank you to all the kind folks that helped me through this.

It took right at 100 gallons of 6% bleach to burn off all of the ammonia in my pool. From May 16th to May 20th I pretty much cleared out the shelves of the local Wal-Marts and Targets of bleach. It was all a bit of a hassle, nightly going through a regimen of testing, plugging values into the Pool Calculator, adding horrendous amounts of bleach, and then doing it all over again 1.5 hours later, seemingly ad infinitum--all this while getting ready to take the family for a week's vacation. But the pool has never looked better and I have never felt more comfortable with understanding what is going on with the water. And, I'm not throwing money at the local pool store!! I am profoundly grateful to this site and all the folks that helped. Thank you.

Today, I put my money where my mouth is and I donated to TFP, because of the help and support that I received here. It was truly a bargain. You guys rock, and thanks!
 
Congratulations! :party:

100 gallons of 6% bleach in 23,000 gallons is almost 270 ppm FC so could have been a bacterial conversion of somewhat more than 100 ppm CYA (not counting any nascent algae that might have developed).

If you had gone to a pool store, then they would have likely sold you non-chlorine shock at 2-3 times the price of chlorinating liquid or bleach for the amount needed to clear the pool and you would have had false CC readings to deal with. If they had sold you Cal-Hypo, then this might have been roughly the same price for chlorine, but your CH would have increased by around 200 ppm. If they sold you Dichlor ( :shock: ), then your CYA would have increased by almost 250 ppm and this would have been more expensive as well.

The only other option that might have been less expensive and/or less work would have been a partial drain/refill, but that depends on the cost of water in your area.

Richard
 
I actually did do a partial drain and refill as all the salt from the chlorine caused the SWG to light up the high-salt indicator (the salt level was a bit high to start with, ~5,000 ppm). We'll see what the water bill is this month! As for the pool store, whenever I would go in with my water, they would recommend a massive shock, but they couldn't ever tell me why that was needed, what the shock was going to do, or how I would know when I was done. Of course, their massive shock wasn't nearly massive enough, as it turned out--a Hiroshima vs. Bikini Atoll analogy is appropriate--but without an understanding of the problem I wasn't going to just blindly dump chlorine in the pool and hope for the best. And yeah, all they wanted to sell me was lithium shock at >$5/lb. I remember asking one time about liquid shock and how that compared to other kinds of shock, and was told that I didn't want to bother with liquid shock. Turns out they don't carry it because of limited space for inventory.

Because of TFP and the wonderful support I received here, I understood what I was up against and gained a understanding of what success would look like quantitatively: "In God we trust; everyone else--bring data." And so I say again, thanks for all the help.

mkenyon2 asked for a picture. This is my oldest daughter Hannah enjoying our BBB pool, courtesy of TFP:[attachment=0:2q5tk6da]Hannah In Pool Web.jpg[/attachment:2q5tk6da]
 

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