Low chlorine reading...but crystal clear? NEVERMIND IDIOT

[akenis]

Came home to the pool (gone 5 days) and a hint of green, some darker growths around the edge, and 0 chlorine. The skimmer was rather full of debris (3 dead frogs) and limited effectiveness of my swg.

Didn't have time (leaving again) to do the full shock treatment, so I just added some of the polyquot (recommended in the stain treatment).

Return 3 days later, and pool is crystal clear, but still less than .5 cl level.

Dumped in enough chlorox to come up to 5 ppm, but tested right away and only measured about .5 ppm. CYA was about 70 a month ago.

1) What does the polyquot, how does it work? Is it masking a lurking algae growth?

2) How long after adding chlorine should u wait to get accurate reading?

3) Should I ignore the pleasantly sparkling and clear water and do the full shock treatment? or give it some time to see if I can make it up to and hold 5 ppm?

Thanks.

 

[JasonLion]

Re: Low chlorine reading...but crystal clear?

1) Polyquat binds to algae, killing it. This process consumes the polyquat. It works well when you don't have much algae, but tends to get used up too quickly when you have lots of algae.

2) Wait at least 30 minutes with the pump running before measuring the FC level.

3) Yes, you need to shock. You need to keep adding chlorine until you can maintain an FC level overnight. Since the water is clear, that probably won't take very long. With a little luck and a little work it is likely that FC will hold overnight tonight.

 

[akenis]

Re: Low chlorine reading...but crystal clear?

Thanks.

That's what I thought..better safe than sorry.

It was @ shock level, 16ppm, at 7pm last night. Down to 13.5 by midnight. Topped it off at 16.5 for the night. Didn't get to check until 9am...12.5 reading. So I lost about 4 ppm over night and the first few hours of sun. 0 CC! Looks great. What do u think?

Will keep at shock for a while I guess, but the kid are coming over. Maybe I'll bring it down to about 9 so they can swim. And then do another overnight test....and set an ALARM!

 

[frustratedpoolmom]

Re: Low chlorine reading...but crystal clear?

Let em swim, shock tonight, repeat the overnight test.

 

[akenis]

Re: Low chlorine reading...but crystal clear?

I'm an idiot...

Did the overnight test again. Kind of weird. Shocked to 16 (assumed) around midnight, didn't test till about 2 am and got a 12.5 reading. @730am got 12.0, w/ 0 CC. So I consider that no drop.

2 days later I test w/ the little Chlorine/PH kit..... .5 Chlorine

Something's not right...do a test w/ FAS/DPD and don't even finish....turns bright red instantly?

Looking a little more closely at the small Chlorine/PH kit, the yellow bottle says R-003. Why is that the same as the reagent in the FAS/DPD (full chlorine) test? Read the instructions...use R-006.

I had just ordered a full replacement set of chems for my kit. Inadvertantly replaced the similiar looking bottles.

So I bet the bromide in my spa is a lot better also!

 

[chem geek]

Re: Low chlorine reading...but crystal clear?

Looking a little more closely at the small Chlorine/PH kit, the yellow bottle says R-003. Why is that the same as the reagent in the FAS/DPD (full chlorine) test? Read the instructions...use R-006.

R-0003 is used to do the Combined Chlorine (CC) part of the test for DPD and FAS-DPD chlorine tests. R-0600 is the OTO chlorine test indicator dye. So yes, using the R-0003 by itself would not show any chlorine since it is not an indicator dye. The components of the TF100 test kit are shown in this post.