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waterbear
07-02-2013, 10:25 AM
Not sure I'm following you... Do you mean I should read the oto test after 10 minutes and that should give a tc reading that will match immediate dpd results?
Yes
Also, I don't know if this adds another piece to the puzzle or confuses things further, but I just tested the CL again about an hour after adding 192oz of bleach. I pulled a sample from the pool in a measuring cup like I always do and ran the same dpd test 4 times with 4 completely different results:
1. Fc 5, when I added r-0003 for cc the sample turned a light yellow, not pink. I have had this happen once before, so I retested (assuming I did something wrong)
DPD bleachout caused by high chlorine levels
2. Fc 22, cc 1.5... Huh? Retest again...
Probably close to what your levels actually are but still bleaching out a bit.
3. Fc 7, cc light yellow/peach????
DPD bleachout caused by high chlorine levels!
4. Fc 15, cc 7
All 4 tests were done within minutes from the same sample of pool water, and I rinsed with filtered water between tests. This stuff should be pretty simple, and I'm a pretty smart guy, but I am completely lost here.

Try diluting a sample of pool water with an equal amount of distilled water and testing that with the FAS-DPD test and multiply that test results by 2 to see what you get.
Re: the autocover...are you leaving the pool uncovered? If a pool is kept covered it is not uncommon for there to be a persistent high CC problem since there is limited offgassing of the disinfection byproducts and exposure to sunlight also is an integral part of the process of destroying CC (which is why persistent CC is a problem in most indoor pools!)

Themadczar
07-07-2013, 11:38 PM
It's been a week since I replaced the water in our pool... We've been swimming almost every day, fc is holding overnight, cc is almost non-existent, and the water has been clean, clear, and comfortable (no stinging, or strong odor despite "dangerously high" chlorine levels from 3 to 12 ppm). I've been dealing with the high alkalinity by CO2 outgassing and adding muriatic acid to lower ph. Seems to be working well. Bottom line though, we are thrilled to be finally enjoying our pool! thanks for all the help here. I will be around, helping when I can and asking questions as they come up.

Themadczar
08-05-2013, 12:35 PM
Final update:
Kudos to Pool Doc, Watermom, Chem Geek, and all the others who helped. It has been 1 month since I replaced the water in my pool. Using the BBB Method, my pool has been crystal clear, and guests have all commented on how nice the water is (no chlorine smell, no burning eyes, sparkle, etc.) The method works; this forum is invaluable; and the people here are extremely helpful. Thanks to all. Now, who has any ideas about making summer appear in NW Indiana? It's August and I've had to run the pool heater several times in the last week!

PoolDoc
08-05-2013, 03:07 PM
Thanks for the feed back.

For what it's worth, last spring was the 2nd or 3rd hottest in the eastern half of the US; this spring was the 2nd or 3rd coldest. And, I know this summer has been the coolest I ever remember -- I think we've had 3 or 4 days when it's reached or exceeded 90 degrees. Normally, it hits the 90's most days in July, and every day in August!

One of the counter-explanations for some of the weather observations the media likes to blame on anthropogenic global warming, is that we are ending a period (century? I forget) of unusually consistent weather, and re-entering erratic weather patterns more typical of the last several millenia.

Regardless, I actually like the weather we've had -- mild winter AND summer, though I could do with a bit less rain. But, it's been very hard on the pool business. Pool builders in this area have had a very poor pool season.

BigDave
08-05-2013, 06:30 PM
It's Global Warming, Global Warming, Global warming causing the sky to fall. Human induced, perhaps; but the sky hasn't hit my head too hard... yet.

Themadczar
08-05-2013, 09:45 PM
Normally I would agree with you, Ben, and I would be enjoying the mild summer (and it has been nice not to need the a/c). However, we put an offer on this house in April last year and drooled over this pool all (HOT) summer long. Finally closed on the house late October... Then this spring it took 2 months to get the pool in swimming order... Now we just want to SWIM.
:-)
Many years of enjoyment ahead though. And we are enjoying every minute we can this season... Even days like today when it was mid 70's outside, cloudy and breezy, my daughter and I were in the pool.

PoolDoc
08-05-2013, 10:27 PM
However, we put an offer on this house in April last year and drooled over this pool all (HOT) summer long. Finally closed on the house late October

Bummer.