Newbie question -- chlorine readings

[jcarithe]

Hi all, new member but have been lurking since my pool was finished in March. I've gotten lots of good info here, great site! Got a question now I can't find the answer to though. As a new plaster pool, running a SWG, I've been adding at least a couple cups of acid about twice a week (ph stays around 8), which I understand is normal. Water seems very clear to me. Went to buy more acid today and took a water sample to Leslies, which I've done probably once a week for the last month or so (but this time a different Leslies). Anyway, was told for the first time today I have no chlorine! I've also been testing regularly (the 5 drop OTO test), and chlorine comes back a pretty dark yellow, so much so I turned the SWG from 30% to 25% a few days ago. Came right home and tested again, still dark yellow, I'd say around 3.0, same as since we first added salt. Had a neighbor come over with test strips, he also said I have no chlorine. So do I have chlorine in the pool or not? Why does my test kit say I do but 2 other tests say I don't? It rained a bunch a couple days ago, and I also added some water after the kids and some friends splashed around all afternoon sunday, could the chlorine have gone way down? So confused!! Any help appreciated.

Thanks!

 

[JamesW]

Your chlorine is too high for most test kits; it will bleach out the reagents and read as zero. OTO does not bleach out. You should get an FAS-DPD chlorine test kit for the most accurate results at all chlorine levels.

http://tftestkits.net/FAS-DPD-Chlorine- ... t-p47.html

http://tftestkits.net/The-TF-100-Test-Kit-p4.html

 

[woodyp]

The rain diluted it, the splashout diluted it,.......and it's gettin' hotter which should cause more FC to burn off along with people in the pool. Do yourself a BIG favor for owning and caring for your pool and purchase one of the two test kits recommended in pool school. The accuracy and ability to read high concentrations for shocking of the chlorine test alone is reason enough. Test strips are the worst. Welcome aboard.

 

[jcarithe]

Wow, thanks for the lightning fast replies! So my chlorine is actually too high? Is that going to cause me problems? How can I bring it down? I'll definitely get a better test kit, it's a big investment and I want to take care of it. Plus the kids have been in every chance they can and water still in the low 70s, I can't afford any down time or I'll have a family mutiny!

 

[dmanb2b]

Welcome to TFP It's may or it may not be too high. Folks are just guessing, but getting that TF100 at Tftestkits.net or the Taylor K2006 should be you first step. If you haven;t done so, check out pool school (link in my sig)...especially the articles below

pool-school/read_before_you_post
pool-school/pool_test_kit_comparison
pool-school/pool_water_chemistry
pool-school/bbb_for_pools
pool-school/water_balance_saltwater_generator

 

[JamesW]

The proper level for your FC (Free Chlorine) depends on your cyanuric acid level. Pool School has a chart of where to keep your chlorine based on the cyanuric acid level. The FAS-DPD chlorine test will be able to tell you your exact chlorine level to 0.5 or 0.2 ppm.

You can lower the FC by turning the SWG off until the FC drops to the correct level.

 

[lightingguy]

It's fair enough to say we are guessing - but high chlorine seems to be a reasonable answer. But you are never going to know without a FAS-DPD test kit. Why the local Leslies doesn't use one is a mystery - but it's a fact. Their test equipment is nothing more than a strip test "read" by a computer.

Of all the things I've done with my pool - by far the best investment I've made is the test kit and taking the time to learn how to use it.