Shocking and some other questions??

[pzmotorsports]

Hello everyone, well it has been about 6 weeks since I took over the pool maintenance. I was overseas since it was completed two years ago.
My initial readings almost 6 weeks ago were:
FC 3.5
CC .5
PH 7.5
TA 90
CYA 90
60 degrees

The cc level went from .5 to 1.0 within the last few weeks. My water is murky and more fine dirt seems to settle at the bottom.

Todays numbers:
FC 1.0
CC 1.5
PH 7.6
TA 100
CYA 50
72 degrees

Not being too familiar with the readings the high CC slided by, I have been cleaning the pool and adding bleach as needed but nothing else, since I thought everything was good. But the last 2 weeks even after cleaning it, it still looks murky and some fine dirt settles at the bottom even after cleaning. I read the shocking article but I'm not clear on how to add the bleach and how much of it? Do I need to start this process early in the morning in order to monitor it? I am backwashing every other week and have noticed a few water bugs swimming in the pool!

Also I want to share the set up of my pool timer and see what you think, it is a dial type and its set to turn on at 10am and shut off at 5pm.

I will like to thank everyone for the help!

 

[PaulR]

Regarding amounts, the Pool Calculator is your friend... plug in your gallons, current numbers, targets, and away you go.

Now about those numbers... Did you replace about half the water in the past 6 weeks? because your CYA went from 90 to 50, and pretty much the only way to do that is water replacement. Or testing error.

According to the Chlorine/CYA Chart, if your CYA is 90 then you need to shoot for FC around 10, and never go below 7. If your CYA is actually 50, then your goal is more like FC 6 with a minimum of 4. You've been below even that all along, so really you are in a place where you need to shock. (You knew that, but I wanted to explain why.) Again referring to the chart, you have a shock level of FC 35 (for CYA 90) or FC 20 (for CYA 50). Obviously you really need to nail down what your CYA is, so you know what your FC levels ought to be. There are a number of descriptions how to do the CYA test around the forum; helpful hints include (a) do it outside with your back to the sun, (b) after you take a reading, pour it all back in the mixing bottle and take another reading. (I usually do 3 to make sure I'm being consistent.)

When you shock with bleach, you add it pretty much the same way as your regular dose; pour slowly in front of a return with the pump on. Except it takes longer when you have to add more.

Filter run times are somewhat of a matter of debate, really the answer is you need to run it "enough" to keep the pool clean. 7 hours is probably not unusual for a pool like yours when it's clean and balanced. Currently yours is not so you should run it more; 24/7 is not out of the question.

So, be ready with your bleach bottle and handy TF-100, and you can clean up this puppy.
--paulr

 

[pzmotorsports]

Paul thanks for your advice! I went and did the CYA test one more time following your advice and triple checked it for a reading of 60, which gave me a shock of 24 FC.

It was a little confusing at first but using the shock recommendations for 60 CYA I went to the pool calculator and entered the current FC and the shock number and I need to add 1,274 oz or 10 gal of bleach.

I will run the pump non stop and start by adding about 3 gallons I have on hand then run and get the rest. Do I need to wait between every gallon or can I slowly but steady add the entire amount?

Thanks again!

 

[PaulR]

No need to wait between jugs, just pour each one slowly enough that the return jet is able to kick it around. Here's a tip for doing whole jugs: Take the cap off, then set the whole jug into the water so it's just kind of floating there upright, and it's really easy to control the pour.

You should give the pump at least a half hour, maybe an hour, before you recheck the FC/CC. Then you keep the FC topped up at shock level, as often as is convenient.
--paulr

 

[pzmotorsports]

You should give the pump at least a half hour, maybe an hour, before you recheck the FC/CC. Then you keep the FC topped up at shock level, as often as is convenient.
--paulr

Paul a quick question on your quote, once I added the 10 gal of bleach and it has been running for 1 hr, then I re-check to ensure I am at 24 FC correct. When you say keep it at shock level, how long will it stay at the shock level with the amount of chemical I have added and will the pool level it self out to the recommended FC and CC levels after a few days on its own? I will run the pump for 24hr until things are taken care of.
Thanks for the great advice!

 

[PaulR]

The question is not how much you added, but how much gets used up killing off the crud in the pool. You keep replenishing what gets used up until it stops getting used up, as determined by the Overnight FC Loss Test.

After you're done shocking, yes you just let the FC drift back down to your target level on its own.
--paulr

 

[pzmotorsports]

I will add the necessary chemical and check the FC an hour later. Also at the end of the day do the FC loss test, if it does not hold the shock by the morning then continue to shock until it holds!

It is a learning experience but once I do it, it will not be that bad the next time, hopefully never again.

Thanks for your help Paul!

 

[Bama Rambler]

Just keep in mind that chlorine is a consumable in your pool so you'll constantly have to keep adding it via some method to maintain your FC. While the amount you have to add will drastically reduce after shocking, you will have to add some amount each day. I use about 1½ quarts of 6% every day to maintain my FC at 7 ppm with a CYA of 50ppm. I use a Liquidator to do the dosing but it would be the same if I were pouring it in by hand or pumping it in with a pump.

 

[pzmotorsports]

Thanks Bama for your tips!

 

[pzmotorsports]

Hello everyone, today is the second day of shocking my pool. Yesterday I got it to 24 FC and at the end of the day did the Overnight FC Loss Test and my results were 16 FC, I am just finishing the morning test and the results are 13.5 FC which means it is killing something in the pool, correct? Please correctly if I am wrong on the next step, I am getting more bleach to bring the level back to shock 24 FC and test hourly to see if it holds.

The water looks way better but it is still not crystal clear, I have been running the pump 24hrs. I am noticing some tan spots that look like rust, I guess because the bleach, but it is only at some of the corners. Also I had some light dirt at the corners as well and I vacuum them it but for some reason they come back? Looks like very fine sand? How am I doing?? Thanks!

 

[duraleigh]

pz,

You're doin' fine.

I would suggest you do not need to test every hour at this point. On the initial application, it is a very good idea because the FC is depleted so quickly. From this point the FC loss will slow down somewhat and I think you could test and bring it back up to 24ppm once in the AM and once in the evening. Either way is fine but twice a day won't be quite so labor intensive.

The important idea is to keep replenishing back to that 24ppm point until your pool is really sparkling. Don't worry for now about the "dirt" I suspect that may be dead algae you are killing. Just keep vacuuming when you can, brush the sides of your pool from time to time, and backwash if your psi gets high enough.

Once your water is sparkling, we'll walk you through the overnite FC loss test and you'll be finished with shocking and can let the FC drift down to it's normal level.......keep it up @ 24ppm for now.

 

[frustratedpoolmom]

Ditto - sounds like dead algae
You can figure out the stains later
shock morning and evening.

You are doing fine

 

[pzmotorsports]

Thanks everyone , I will keep up the FC as directed and follow your advices!

 

[pzmotorsports]

Finally got things stable! Did the FC test last night and early this morning and it is holding steady at 6.5 FC. Went ahead and moved the timer from 7 hrs to 8 hrs. I figured if our pool keeper lady kept it at 7 hr for the winter then 8 hr should be better for this hot weather. Now I should test the CYA and stick to that number in order to keep up with the FC, correct? I was told by our pool keeper to add between 1 and 2 gallons of bleach a week, that is about 1 QT per day.

Thanks again to everyone, my wife was thinking on calling a professional, I said slow down I got TFP :-D

 

[frustratedpoolmom]

Yes, test the CYA and then refer to the chart for your recommended FC target/min levels. 1qt sounds about right, not sure - just give that a go and see how much 1qt raises the FC in your pool. In the evening, you test, add the bleach, wait an 30-60 minutes and test again. If it raises it by 2-3 ppm then 1 qt should do the trick. Some days it may be more, some days less.
Congrats!

 

[Butterfly]

Well, if your pool is indeed 26K gallons, I think it might take appx 3.5 quarts to increase your FC by 2ppm.

My pool uses between 2 & 3ppm FC daily in the summer, but every pool is different

You can use Jason's Pool Calculator to play with the numbers ( Link in my sig).

There is an "Effects of adding chemicals..." section near the bottom.

 

[frustratedpoolmom]

Joyce is right, 1 qt is about right for MY POOL, LOL I wasn't paying attention to the size, my brain was elsewhere this afternoon....

 

[pzmotorsports]

Thanks once again for the great advice! I beleive my pool is 26K, that is what the pool calculator told me I have been using this number for shocking so I guess it can't be that far off. I will test this afternoon and go with one 1qt of bleach as a starting point. The whole family is loving it, nice and clear :lol: Thanks again everyone at TFP...