Steps - Switching from Baquacil to Chlorine

[Watermom]

Sounds like you are so close, but I would do another day or two. Better than stopping a little short of the final goal.

[GeneNTN]

Wednesday, June 1st 6 a.m. - Day 7

Our pool continues to become clearer (by looks anyway), with still some debris laying on the bottom. Yesterday’s results were basically a repeat of Monday, except with testing spread out to every 3-4 hrs with a total of 14.34 gallons of chlorine (bleach 6%) added. Again the FC level did vary a little more during noon / afternoon hours and the CC level stayed basically the same (0.75 – 0.5 ppm). Overnight the FC level did drop by 1 ppm (maybe due to testing?) and the CC level remained unchanged (0.75 ppm) – which prompted a question as to why no change since Monday’s p.m. test? I contacted Taylor and asked them if there was a procedure to test the CC level independent of FC, using a 25 ml water sample (0.2ppm resolution)? The answer I received back was “Taylor does not currently offer a method for testing combined chlorine independent of the free chlorine result. To my knowledge, I am not familiar with another company that does.” - which seems a bit odd to me? Does anyone on the forum have any comments or concerns about their reply?

With all of the repeated testing, I need to immediately re-order the reagents for the chlorine testing! So plans are to do the dosages of chlorine (bleach 6%) - based on my records from the past 2 days, and only test 2-3 times / day, especially for 8 p.m. today & 6 a.m. tomorrow.

Watermom!
I do agree with your recommendation, another day to see if the CC will ever go to lower? Thank you for your response & have a great June 1st!

Gene

[madwil]

I think, with regards to testing CC, the issue is FC causes errors in CC reading; so you have to remove the FC first, without overdoing it, before you can test CC.
I think, at your current readings, you're safe to change out sand whenever you want- but maintain shock levels of FC until your CC is <.5.

[GeneNTN]

Madwil,
Thank you for your comments - they are always helpful!
When you say, “remove FC first” I assume you mean by adding the R0781 drops until the water sample is colorless, which is what I have been doing. However, if there is a short time delay (making notes, etc.) until the 5 drops of R-0003 are added – the water sample will usually take-on a pinkish color? So…would you just add the R-0003 or go back and add some additional drops of R-0781? Would you happen to know of a better method of testing the CC at the lower end?
Gene

[madwil]

if the color comes back after the delay, I think that's the reagent beginning to react with CC- the reason why OTO only gives TC...
You do not have to go back and add addtional 0781- just continue the test as you have been doing. I do not know of any better way- Chemgeek or Waste may...

[CarlD]

That IS confusing. What you do is test the water sample for FC using 0870 powder and 0871 drops. Then TO THAT SAME SAMPLE add the R-0003, 5 drops. The water should turn clear if there's no CC, pink or red if there's some CC. Now use the 0871 drops AGAIN until the water goes clear to measure CC.

That's it!

Carl

[GeneNTN]

Madwil & Carl,
I follow the Taylor instructions per the letter – and do not repeat any of the previous steps. I guess an answer would be to use a 25ml water sample to begin with, which in turn would provide a 0.2ppm / drop of R0871 when testing for ‘lower levels’ (<= 0.5ppm) of CC. However, I will have to wait on my order of reagents (R0871 in particular) to try this method. I’m sorry if my previous posting was not real clear? Thank you and have a great day!
Gene

[madwil]

sorry if I was confusing- yes, you have to use the 25ml sample for the FC test, to get .2ppm results on CC (after completing the FC test)
I think that for most people, getting .2ppm results is probably not necessary- curiosity maybe, or chemgeek when experimenting for science...
But for me, <.5 is good enough on the CC, and my FC stays above 5 normally so not going to use that many drops to get it to .2 accuracy!