Baquacil conversion with percarbonates

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In the test kit that I have.....to test for FC, I added the powder and the solution turned pink (indicating chlorine in the water). We then added the drops one at a time until the water turns clear......right? The first time, I stopped at 60 drops (30 ppm FC).
The second time we stopped at 40 drops (20 ppm FC).
The water never turned clear.

When do I expect goo?
 
To confirm, you are adding drops of R-0871, correct? Did you order the TF-100 or a k-2006? If k-2006 can you give us the lot number of the R-0871?

Something has to be wrong with the test, even if you are using 12.5% 4 gallons would only raise your FC by 26 ppm. Just need to figure out what.
 
Are you using 10 ml or 25 ml of pool water for the test? Be sure to use 10 ml. Count your drops and divide by 2 for FC.
 
In the TF-100 there's a small blue box (K-1000) that tests Chlorine and pH. Can you use that to test your Chlorine quickly? Let me know what color you get.
 

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Adding only 3.5 gallons will only take you up to 15ppm in your pool. Something isn't right somewhere. The oto test shows you have very little chlorine which I am guessing is correct.

Can you try both the OTO (blue box) and the FAS/DPD test again. Let me know what colors you are seeing.
 
So after doing some searching and reading, I came to the conclusion that my CC levels are so high that they are interfering with the FC test.
When I did the FC test, the first 20 seconds or so after putting the powder in were clear indicating that my FC is 0.
I started adding chlorine again, every hour and with the last water test, I think my FC was 3.5 (the water became clear for just a second before turning pink again and when adding more reagent, the water remained pink).
I have added a total of 15 gallons of chlorine today (the last being 2 gallons at 10 pm).
I will test in the morning and get back to it.
 
I'm back...Leebo alerted me to what you've been going through.

So there are two interferences here going on with the DPD test. You have high total oxidizer levels (peroxide + chlorine) and both will register on the FC side of the test. With combined chlorine there can be two interferences - if the CC levels are extraordinarily high, you can get CC breakthrough on the FC side of the test (as you learned about) and that will register as excess FC. Also, if you add the potassium iodide (R-0003) reagent to do the CC test, the excess peroxide with convert the iodide into iodine in proportion to the peroxide level, and you'll see HUGE CC numbers. One way to fix this problem is to dilute the sample. I would suggest diluting the pool water sample with distilled water in a 3:1 ratio (3 parts distilled water to 1 part pool water) and then measure a 10mL sample. You still use 0.5ppm/drop but then take your final answer and multiply by 4. If you have to, you can also use a 5mL water sample which is 1ppm/drop but again multiply by 4 if you use a diluted volume.

Leebo gave the right advice, use the OTO indicator to measure total chlorine for now. You're going to have to do some crude analysis with it and wait until you start seeing deeper yellow colors on that test before you can trust the DPD test. Right now the peroxide and chlorine are destroying one another and it takes multiple applications for the chlorine to neutralize all the peroxide and then, when the peroxide is all gone, the chlorine can start working on the biguanide.

It's encouraging to hear that you're not seeing a lot of color to the water. When only chlorine is used to destroy biguanide, you gets lots of yellow, green and brown colors from the chlorine oxidizing the biguanide polymer into smaller sub-units. High peroxide levels also destroy biguanides but with no color changes. So, perhaps, the peroxide did some initial degradation of the biguanide and maybe chlorine will have an easier time at it....time will tell....
 
Good morning. I am up and back at it this morning. Overnight, the pool has remained green in color but I now have a nice layer of yellow film floating on top of the water. There is quite a collection of it in the skimmer but it seems not to be going down through, jut remains on top. I've been skimming to try to get as much out as possible
OTO test this morning was low (as I would have expected) at 0.5 so I added another 3.5 gallons.
I emailed Lee my picture from this morning so it can be posted.
 
Skim as much of that as you can from the surface to physically remove it from the pool. That's your oxidized Baquacil (aka, baquagoo). You're doing the right thing - keep adding chlorine until you see it hold. Also, you can try run a diluted test using the DPD kit to see where your total oxidizer level is at. I would only do a high dilution at first to save yourself from using too much reagent.
 
We are making progress.....
My last water reading (using the dilution) was:
FC 16
CC 11
I know the FC is up there but we have been slowly trending up.....first 3, then 6, now 16. Between each, I was still adding 3 gallons of chlorine trying to get the levels up there.
Also the last hour was the first time I put chlorine in without seeing a trail of color where I put it in.
I continue to skim the goo off the top.
I still have the filter set on recirculate and will continue to keep it there. Can I assume that once the pool starts to clear my next step is to vacuum to waste?
 
What's the OTO test showing?? Faint yellow or tweety-bird yellow or burnt-orange??

Well the pool won't really clear with the filter in recirculate. I would wait until we get a more definite feel for your water holding chlorine levels and then you can vacuum-to-waste anything on the bottom and switch to filter mode. But yes, eventually we have to start filtering out all the gunk you can't scoop up with a leaf net.
 

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