Steps - Switching from Baquacil to Chlorine

[madwil]

it looks like your FC held overnight, but with reading increasing concerned with if you added something after the 830pm reading?
if not, your FC should not have increased, but at 6am I can't count drops (I get up at 5, can talk, but no testing until after 1st POT of coffee!)
your CC is slowly going down, which is typical- keep the shock level of FC another day or two, until you lose <1ppm FC overnight, and CC is <.5
Then change out sand and you have successfully gotten rid of BaquaGoo!

[GeneNTN]

Madwil,
Actually, I did not add any more chlorine (bleach 6%) after the 4:30 p.m. reading – my guess is two fold, 1) the overall total chlorine added for Monday was ~ 19 gal., and 2nd ) with the periodic brushing of the sides & bottom (filter passage, sock in skimmer basket, etc.) – it took an extra amount of time for the FC to rise! Beyond that thought I’m kind of struck as to why as to why it increased overnight?
Your recommendation to continue for another day (or 2) is in line with my thinking – although today I have not been as punctual as I was yesterday – a holiday! I’ll be very happy to finally get ride of the BaquaGoo!

Gene

[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