Having trouble with Chlorine

SummerDay123

Member
Jun 26, 2020
13
Long Island, NY
Hello Forum!

I'm about ready to give up on my pool :( I can not balance the FC and CC, I've been trying now for a week. I do have the Taylor 2006 test kit but I have used the Oxidizer (potassium monopersulfate) from the pool store which I read can give inaccurate CC readings, so I've been going to the store for my testing these last few days. (I did order the reagent for that but it's going to be 2 weeks before it gets here). I've been to the pool store three times in the last three days and I'm really ready to quit. I don't have liquid bleach right now so I'm using the pool store chemicals.

Here are some of my readings:

On Saturday my readings were:
FC .35
Total C 2.92
PH 7.8
Alkalinity 82
Calcium 75
CA 32

They suggested the oxidizer (potassium monopersulfate) which I used (5 lbs). Went back to the store on Sunday:
FC .46
Total C 4.48
PH 7.5
Alkalinity 80
Calcium 79
CA 36

(I do have a few of those chlorine tabs in the pool floating device)

Since my FC didn't go up on Sunday, the staff were confused and I decided to wait for the manager, so went back on Monday:
FC .26
Total C: 2.14
PH 7.7
Alkalinity 81
Calcium 74
CA 34

He suggested the Calcium Hypochlorite, which I added 5 lbs. He told me to come back on Wednesday for a new reading. But since I have the test kit, and can test my own FC, I took a quick look and FC is non existent. I put the powder in the sample water and it barely turns pink. How is this possible? I tried 5 drops of the #3 reagent just to see what the CC would be (knowing it might be wrong) and it's super light pink. Like 1 drop and it's clear. How can I have no chlorine in the pool? I'm clearly totally lost :(
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Okay Summer, here's the issue ..... the pool store. Plain & simple. Don't fret, don't panic, you got this. You have a K-2006 test kit. Trust YOUR numbed not theirs. As for the FC specifically, use liquid chlorine or regular bleach only. Don't use any MPS pool store powders and stuff. What kind of pool do you have? Please update your signature details. If you have vinyl, you don't need any calcium.

For now, find some liquid chlorine at Walmart or Home depot, maybe Lowe's. If not pool chlorine at 10% strength, then regular laundry bleach (plain, not scented or splashless). Avoid the Clorox bleach. Use the PoolMath APP to determine the dosage and increase your FC to about 5 ppm. After adding, test again in about 30 minutes to see how it's doping and report back if you see problems.
 

carnivalday

Gold Supporter
Bronze Supporter
Oct 25, 2017
581
Ocala, FL
What Texas Splash said! Take a deep breath, relax, "step away from the pool store". Do what TS advised, ask any questions if you dont understand something, and these guys will get you quickly to where you need to be. :paddle::paddle:

Where did you order the reagent from that it will take 2 weeks?
 

SummerDay123

Member
Jun 26, 2020
13
Long Island, NY
Thanks for the replies! I have only seen the liquid chlorine at the pool store (ironically). The pool store sold them in boxes of 4 gallons and it was too heavy for me (i'm small), I'll have to go back and get it.

what's interesting though, is I just tried out the pool calculator for slamming with calcium hypochlorite at 73% (which is what I used yesterday), and it says 4 lbs. I put in 5 lbs yesterday, so I had more than I was supposed to. I added that last night around 6pm, by 9am there's no chlorine, Where did the chlorine go in 15 hours?
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Where did the chlorine go in 15 hours?
Two things could explain that one. First, FC can drop quite fast when algae is present. Second, we need to see your K-2006 test kit results because even though all 3 pool store tests appeared to be close to 30, we trust YOUR testing above all else. If your CYA is slightly low, the sun will burn-off the FC as well. But with the right test kit and plenty of folks here to help coach you, this is the best place to be. Once you get the liquid chlorine, add the required amount and test again in about 30 minutes. You may be catching this algae thing just in time.
 

SummerDay123

Member
Jun 26, 2020
13
Long Island, NY
Ok I bought the liquid chlorine. I'm on team TFP!
I tested the water earlier:
FC 0
CC .2 (but probably less)
PH 7.4
Alkalinity between 70 and 80, maybe 75
CYA 30 (but maybe a smidge higher)

So, I took your advice and added enough liquid chlorine to bring the FC up to 5ppm (using pool math). And waited 30 minutes and retested, here are the results
(i'm running low on drops so i switched to 10ml samples)
FC 4.0
CC 0
(do I need to retest all other points?)

Hoping that's good news so far. What should I do next?

Thanks in advance!! I'm hopeful :)
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
It is good that you are holding some FC, but I suspect it's still dropping a bit fast. So now we need to determine if the FC drop is from lack of stabilzizer (CYA) or algae. So please take a good CYA reading at home. Use my note below it help. Let' s see what you have for a CYA.

CYA Testing:
Proper lighting is critical for the CYA test, so you want to test for CYA outside on a bright sunny day. Taylor recommends standing outside with your back to the sun and the view tube in the shade of your body. Use the mixing bottle to combine/gently mix the required amounts of pool water and R-0013 reagent, let sit for 30 seconds, then gently mix again. Then, while holding the skinny tube with the black dot at waist level, begin squirting the mixed solution into the skinny tube. Watch the black dot until it completely disappears. If it helps, pour a little, look away, then look back and pour some more. Some people like to squirt enough solution to go line-by-line for a better feel. Once it disappears, record the CYA reading. After the first test, you can pour the mixed solution from the skinny view tube back to the mixing bottle, shake, and do the same test a second, third, or fourth time to instill consistency in your technique, become more comfortable with the testing, and validate the CYA reading. If you are still questioning your own results, have a friend or two do the same test 2-3 times. Share your results only after everyone is done to see if you came up with the same average results.
 

SummerDay123

Member
Jun 26, 2020
13
Long Island, NY
Ok I tried it quite a few times. CYA is under 30. I filled the whole little tube (past the 30 mark, to the top) and could still just see the black dot. But it's definitely under 30. Should I add some?
 

Enjoying this content?

Support TFP with a donation.

Give Support

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Should I add some?
Yes. But for now, let's go slow. Use the PoolMath APP to increase the CYA by 10 ppm. That way you don't go too high over 30 in case a SLAM Process is required later. Should be around 40 ounces (2.8 lbs) of granular stabilizer, but double check to be sure.

Adding CYA:
To increase CYA via granular stabilizer, place the required amount as calculated by the Poolmath calculator into a white sock and place in the poolside skimmer basket. For those concerned about suction flow to the pump, suspending the sock near a return jet or from a floating device will also suffice. Best never to allow undissolved granules to rest directly against the pool surface. Squeeze the sock periodically to help it dissipate. Once dissolved, consider your CYA adjusted to that programmed (target) level. CYA test readings should show a rise in 24-48 hours, however some pools may experience a longer delay to fully register. Best to confirm final CYA in about 5-7 days before adding any more stabilizer/conditioner.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
What should I do about my chlorine in the mean time? Should I test it again later and add more if necessary to keep it at 5ppm?
For today only, I would test the FC before dinner and then once more just before bedtime. In fact, once you take your final bedtime FC test, take another FC test tomorrow morning before the sun hits the water and compare it to tonight's bedtime FC test. That would be what we call the Overnight Chlorine Loss Test. The OCLT is a great test to see if algae is a potential problem. If you decide the turn off the pump at night, make sure to turn it on at least 30 minutes before taking the morning water sample. Or you can just leave the pump on low speed all night if you can.
 

SummerDay123

Member
Jun 26, 2020
13
Long Island, NY
Hi Splash,
I retested the pool in the evening and the FC went down from 4 to 1.5ppm (CC was .5). I added more chlorine to bump it to 5ppm.
I tested it again at night and FC was at 4.0 and CC .5
This morning, FC was at 1.5ppm and CC at .5, so it failed the OCLT
Should I start the SLAM?
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Should I start the SLAM?
Yes, that is correct. Make sure to review the SLAM Process page once each day as a memory jogger of things to do. Remember before increasing the FC to SLAM level, lower your pH to about 7.2 first. I think your CYA was low before, but if you got it to 30, then your FC SLAM level would be "12" as noted on the FC/CYA Chart. If you find the CYA to be different, then just go back to that chart and use the correct FC SLAM level. Brush and inspect everything carefully for best success. If you have a large light with a niche behind it, remove the light and clean in there as well. If you have a main drain, try to go down there and inspect/clean under the cover. The SLAM Process will work if you follow that page. Good luck!
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
full
 
Thread Status
Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.