Cant hold chlorine

[herrmanncr]

New to sight and need some help cause I ain't getting from the pool store. I can't get my free chlorine up. My pool is in ground vinyl 21000g. Opened beginning of May and still won't hold chlorine. Water is clear. Had a couple bouts with green tint but hit with shock and looks good now. Have not been using tabs for weeks until yesterday. I shocked and added 1 tab. Don't have test kit. Usually use strips or take to pool store and get tested. Had it tested today but left sheet at store. Sundays #'s below.
FC - 0.2
TC - 0.6
CC - 0.4
TA - 130
PH - 7.3 Think it ws 7 today
Hardness 400
CYA - 61 today was 94. don't get it
Sat index - 0.20
Last 3 shocks treated with 2 lbs Dychlor each time.

Somebody please help me get this fixed!

[Watermom]

Hi and welcome! I sense some frustration here! We'll help you get this figured out!

You really need your own testkit so you don't have to depend on the pool store. You can get a good kit which will save you a lot of money in the long run. We recommend either the Taylor K-2006 or the 2006C which has larger quantities of reagents. With a pool that has a high chlorine demand like yours seems to, you should probably think about the 2006C.

Dichlor has CYA in it and that may be why you have the increase, although a 33 ppm change since Sunday doesn't seem likely. Most likely tester error.

How often are you adding chlorine? To get this pool clear, you are going to need to test and add chlorine a minimum of 2 times a day - early morning and evening after the sun is off the pool. But, actually it will clear faster if you will test and add chlorine as many times a day as you possibly can.

I would suggest just using bleach as your source of chlorine. You don't want any more dichlor shock or even trichlor tabs because both of those will raise your cya level even further, which you do NOT want. I wouldn't use cal-hypo because your hardness level is already at 400. Bleach will not raise anything except the chlorine level which is what you need. In a 21K gallon pool, each gallon (4-qts.) of 6% bleach will raise your chlorine level by about 3ppm.

What you need to do is test as often each day as you can and each time, add enough bleach to raise the cl level back up to 20ppm. You want to try and sustain this high level and not let it yo-yo up and down. If you will do this consistently, it will clear your pool. It may take a few days. When you get to the point where you are not losing more than 1ppm of chlorine from sundown to sunup then you can let the cl level drift down and then keep it between 5-10 ALL the time. If you let it dip lower than 5, you risk another algae bloom.

Also, run your pump 24/7 right now.

Watch your pH. You never want it lower than 7.0 or it becomes acidic and will damage your pool. If it drops, add some 20 Mule Team Borax (in the laundry aisle at Walmart).

Hope this helps. Repost if you have further questions.

[peekaboo]

Let me try to help you out.
1)Get yourself a good drop based test kit .Taylor k2006 or Leslie Pool store equivalent are favorites here.
2)CYA-did you drain and refill some water or have a VERY heavy rain because the only way to lower CYA is a partial drain and refill of pool or like if your pool was half filled and rain water filled the rest
3)CYA of 61(if that's an accurate reading )means you needs to keep chlorine at a minimal level at all time(check Best Guess CYA chart on this forum)
4)Sounds like a chlorine demand...means you must keep chlorine at your shock level and keep it there by testing several times a day and adding chlorine to keep it at shock level until you keep yor minimum free chlorine for your CYA level overnight.

I'm just a newb here but I read and reread most of the threads..you can learn alot.

Do you have vinyl liner pool?,concrete?,how many gallons?Can you get water tested again and post results as soon as you get them?I'm sure one of the great mods like Watermom,Carl D,chemgeek or any other will be by to help out any time now.

BTW Welcome!

[herrmanncr]

Thanks. Where can I get that kit. Will stop and have tested this evening. Added 5lbs calhypo last night thanks to pool store. Hardness will be off the chart probably. Only draine 2 inches and filled back. How much bleach do I add at a time. Can u swim with this problem? Been using and no irritation. 21000 g, inground vinyl.
Thanks for help,
Chris

[aylad]

In your size pool, each gallon of 6% bleach will raise the FC by about 3 ppm, so if you're trying to achieve shock level, I'd put 7 gallons of bleach in it. Pour it slowly into the return stream, being careful not to splash it on your liner. I would do this at dusk, since the bleach will have all night without sun interference to start working on your water. In the morning, test again, and add whatever amount it takes to get it back up to 20. Do this 2-3 times a day, filter running and backwashing as needed, and it will clear up. It may take up to several days of this--fixing pool problems is almost never an overnight process--but it will clear. I would NOT use any more cal-hypo, though--your calcium is already way too high, and that in itself can create problems with milky water that are much, much harder to solve than just shocking with bleach.

Two of the cheapest online sources we've found for the Taylor kit are http://www.amatoind.com and http://www.spspools-spas.com. Leslie's online also sells a relabeled version of the same kit.

Welcome to the forum!

Janet

[herrmanncr]

Thanks! I will start on it this evening. Hope it works. This is frustrating!

[aylad]

It will work, but it will take a large dose of POPP--Pool Owner Patience and Persistance!! I understand how frustrating it is, but unfortunately it's a process, and by definition is going to take a little time. I promise, though, we can help you get it clear!!

Janet

[herrmanncr]

What's the rule of thumb when adding Borax? 21000g inground vinyl. Thanks!!!

[Watermom]

Depends on how low your pH is. Yesterday you said that it was at 7.0. If that is still true, in this 21K gallon pool I'd probably add a half a box. Let it circulate for a few hours and then retest. See how much that moves it and then add smaller amounts to tweak it where you want it.

[peekaboo]

darn ,beat by Watermom by 5 minutes

[aylad]

darn ,beat by Watermom by 5 minutes

Yeah, you gotta watch her, she's quick!

Janet

[CarlD]

Gets the jump on me all the time!:mad:

[herrmanncr]

OK, got test kit on order (K2006C). Meantime had pool store test at 3pm.
FC - 0.1
TC - 0.6
CC - 0.5
ALK (adjusted) - 117 (input) - 148 not sure the difference
PH - 7
Hardness - 377
CYA - 92
Sat index - -0.13 don't know if needed

5pm - added 1.5lbs Borax
830pm - added 4 - 1.42 gal bleach (5.68gal) 6% hypochlorite
Will check with strips and add 4 more before work WED morning if not holding. Test kit will take a couple of days so will drop sample off at store and have tested to get #s. Will post them once I have in hand. Again thanks and let me know if this is a good start or anything else to do. 21000 gal ingrnd vinyl.

[aylad]

This is a good start, but you're not going quite high enough with the chlorine to actually burn off the demand. You need to get to 20-25 ppm, since your CYA is so high. Since each gallon raises Cl by 3 ppm, that means you need 7-8 gallons in at first, then to add more at dark and in the morning to get back up to the 20-25 ppm. It will go faster if you can also test and re-add 2 or 3 times during the day.

Since your CYA is so high, you really need to consider draining and refilling about 1/2 your water, because even when you get the chlorine demand worked out, you're still going to have to maintain 8-15 ppm Cl at all times to keep the algae away.


Janet

[herrmanncr]

OK. Checked with strips this morning. FC looked to be about 3 ppm. Added 4 more jugs bleach. Dropped water sample off at pool store for test. Will do another test at 4pm. Will add 5-6 jugs tonight. Thanks.

[aylad]

Let us know how it's going!

Janet

[herrmanncr]

Got some results. At 4am this morning I took a water sample so I could drop off at pool store this morning. Also added 5.68 gal more of bleach. Results from this mornings sample after adding the 5.68 gal of bleach and 1.5lbs Borax last night are:
FC - 1.0
TC - 1.4
CC - 0.4
ALK (input) - 225
ALK (adjusted) - 205
PH - 7.4
CH - 400
CYA - 60
At 4pm today I took a new sample to have tested after adding the 5.68 gal bleach this morning and results are:
FC - 3.6
TC - 3.8
CC - 0.2
ALK (input) - 154
ALK(adjusted) - 130
CH - 292
CYA - 73
I could not believe it held chlrine today so at 5pm I took another sample to a different pool store and results are:
FC - 3.8
TC - 3.9
CC - 0.1
ALK (input) - 114
ALK (adjusted) - 82 what is the difference?
PH - 7.2
CH - 293
CYA - 96
Both stores use the PINPOINT water analysis system but ALK & CYA #s are way different. One store has me listed at 22000g & the other has me at 21000g. Could this be the difference? Also, when I told the "pool guy" I went to this sight for info and was using bleach he was impressed but said the bleach could ruin my liner. Should I be worried? Don't want to get my hopes up but looks like it held. Water is crystal and was 100* here today. Pool gets full sun from 11am to 6pm. What's my next step. Thanks again evderybody!!

[sturev]

You need to still work on getting you FC level up... With your CYA, you really need to be at 5 to 10 for normal and I think the mods might tell you to get it up to 20 to shock it since you've never achived that yet...

[aylad]

The difference in CYA and Alk could well be because of the difference in reported volume, I don't know....

Like Evan said, now that you're starting to hold chlorine, I would shock it up to 20 just to kill off the rest of the CC, and see if that doesn't make a difference in the demand.

The next time you talk to your pool guy that said bleach (which is 6% sodium hypochlorite) would ruin your liner, ask him why liquid chlorine (10-12% sodium hypochlorite) won't? It's funny to watch them hem and haw around that. Bottom line is, they're the same thing, but bleach is half strength, and easier to deal with (and if you're from Louisiana, the key word is AVAILABLE!). Of course, if you splash it directly onto the liner while adding it, it will discolor in those spots, but if you're careful when adding it NOT to splash it on anything, once it gets into the water it breaks down into chlorine and salt water. Nothing there that will hurt your liner, if added in the right amounts.

Looks like you're on your way to easy poolkeeping!!!

Janet

[peekaboo]

poolguys are used car salesman at best.That's like saying dont spin that .38 caliber handgun on you finger it might go off and kill you..you really should be spinning this .44 magnum instead on your finger

[herrmanncr]

Sounds good. I will shock up to 20. Hopefully I get my test kit tomorrow and wont' have to go to pool store. Awesome help. Thanks again!!!

[peekaboo]

BTW sorry if I offended a "good" used car salesman on this forum>I meant to say a "bad,over anxious,obnoxious,about to be evicted,late with the child support,gotta make a sale NOW,used car salesman"

[herrmanncr]

Added approx 5.25 gal bleach 830pm last night. Had wife take sample to pool store at 1130am. Results are below:
FC - 3.5
TC - 10
CC - 0
PH - 7.1
CH - 212
ALK(input) - 149 ALK(adjusted) - 127
CYA - 65
I know I need to add some Borax to bring up PH. Wife is nagging to swim. I said no cause to much TC. Am I correct? Sorry for all the questions.

[aylad]

No need to be sorry!!
Actually, with a CYA of 65, a total chlorine of 10 ppm is the upper range of normal, and is fine to swim in. The CYA being high renders a higher amount of the chlorine inactive, for want of a better word, so while a Cl of 10 with CYA of 65 is fine, a Cl of 10 with CYA of, say, 20 would be too high. Does that make sense?

That being said, otherwise your numbers look good, except there's a problem with your chlorine. FC + CC = TC, so if your FC is 3.5 and your TC is 10, that would make CC 6.5, and you wouldn't have a nice, clear pool. So...either there's a typo in your numbers or you have an inordinately high CC, which I doubt. Can you recheck and repost those?

Janet

[herrmanncr]

My wife says the FC is 3.5, TC says 3.5 (but the pool guy scrated it out and wrote 10) and the CC is 0. Called the pool guy and he said the system won't let him print unless he balances it out. Don't look balanced to me. Can't wait for my kit!! Should we swim?

[aylad]

I'd add a gallon of bleach, wait about 30 minutes, and then go swimming!! The Cl range you need to keep is 5-10 ppm because your CYA is high. If you'll add a gallon now, that should put your TC at 6.5, which is fine. If you let it stay below 5 ppm you're going to have problems keeping it clear. So--add some bleach, go swimming, then test it again (if possible) tonight and add whatever amount you need to get it back up toward the higher end of the 5-10 range.

Hopefully your kit will get here soon and it'll be SOOOO much easier!! (I would ditch the pool guy if I were you--you can't just make the numbers be what the printer wants!! I'd hate to be trying to balance my pool based on his criteria......)

Janet

[herrmanncr]

Got my K2006 last night. Did some testing. Gonna take some getting used to. Added bleach to get back to 20 and Borax to raise PH. Tested this morning 330 am and results are.
FC - 13.5
TC - 14.5
CC - 1
ALK - 160-170
PH - 7.4
CH - 400
CYA - not sure if i did it right(transfer to comparator until black dot disappears). Shows over 100 but pool store yesterday said 65?


So if I'm right I need 6.5 ppm to get back to 20 becuase I'm still losing chlorine right?
If 1gal bleach adds 3ppm then I need to add just over 2gal which I did. How am I doing? This is a pain!!! Thanks

[CarlD]

Actually, your numbers sound right to me. 2 gallons of 6% should get you to 20ppm. But if you have CYA=100, you may consider that the shock level for CYA 100 to 200 is 25ppm. You are still getting a CC reading greater than zero which means you are still fighting something.

I would add 3 gallons then, to put you at around 23ppm, and see if it holds. Plus, you will need to maintain FC between 8 and 15 as long as your CYA is so high.

P.O.P.P: The most important ingredient--Pool Owner Patience and Persistence!

Yes, it's frustrating but high CYA forces one to commit to much higher FC levels than we normally think about.

You may want to consider dumping half your water and refilling to reduce your CYA level to 40 to 50--easier to maintain lower chlorine levels then.

[herrmanncr]

I'm trying not to drain just yet because the different readings between my test and pool store (65vs100) but I will try and raise the FC with more bleach and see what happens. Unfortunately my wife doesn't know how to use the kit yet so I will get her to take a sample to the pool store and get tested this morning and have her add bleach accordingly. Can she use the pool today with such high FC?

[CarlD]

It's not the high FC that concerns me--it's that you still have a non-zero CC (actually, if CC is .5 or less you are pretty much OK).

If the test shows CC is OK (less than .5), it's up to you whether she can swim or not. I tend to think not because I'm conservative, because you haven't yet been able to hold a consistent FC--and with that high CYA level, I would wait until FC holds steady for at least 1/3 of the day. Still, it's your choice. But warn her to use an older suit because the high FC could fade it.

Ultimately, the decision and responsibility are yours. We can only suggest.

BTW, I find that I always run my CYA test the same way: Hold the tube at waist level and face the sun. I move it around a little as I add the fluid, making the dot more visible, so if the dot peeks through I add more. Still, I believe your readings taken immediately from the water with the K2006 before I believe someone in a pool store, probably using strips.

[herrmanncr]

Wife took sample to pool store cause I can't be there to test. Here are results:
FC - 10
TC - 10
CC - 0
CH - 268
PH - 7.3
ALK - 113
CYA - 65
SAT Index - .10

They want to swim so I said add 1gal, wait 1hr and swim. I'll test and treat when I get home.

[aylad]

Those numbers look fine to me--I would swim in it with no problem. Great job!

Janet

[herrmanncr]

All you guys. Will test when I get home and adjust as needed and post #'s. Thanks!

[herrmanncr]

Think I need to shock to 20 or just maintain 5-10 FC as long as no CC and CYA stays down?

[aylad]

As long as no FC is holding steady, CC stays down and no chlorine loss overnight, then keeping it at normal ranges should be fine. Normal range is determined by your CYA, so here's the guideline...
Stabilizer . . . . . . Min. FC . . . . Max FC . . . 'Shock' FC
=> 0 ppm . . . . . . . 1 ppm . . . . . 3 ppm . . . . 10 ppm
=> 10 - 20 ppm . . . . 2 ppm . . . . . 5 ppm . . . . 12 ppm
=> 30 - 50 ppm . . . . 3 ppm . . . . . 6 ppm . . . . 15 ppm
=> 60 - 90 ppm . . . . 5 ppm . . . . . 10 ppm . . .. 20 ppm
=> 100 - 200 ppm . . . 8 ppm . . . . . 15 ppm . . .. 25 ppm

So if your CYA is 65, then 5-10 will be fine--just don't let it get below 5. If the CYA is 100 or greater, then keep it between 8-15 ppm.

If you see CC starting to go up (greater than 0.5 and not dissipated by sun) or the pool starting to look hazy, then shock it again.
Janet

[herrmanncr]

Just wanted to pass on an update. Everything appears to be holding pretty good. Tested throughout the weekend and bleached as needed to maintain. Tested this evening and #s are:
FC - 6.5
TC - 7
CC - .5
PH - 7.2
ALK - 105
CH - 290
CYA - didn't test/out of reagent/this test is diffacult to read/still above 60

Not sure on maintenece dose yet. FC this morning at 4am was 10 and added 1 gal bleach.
Did not add all day and this evening it was 6.5 so added about 1/2 gal. Pool in full sun from 10 to 6/7. Any advise? Thanks everybody for your help. This site is a life saver!!!

[aylad]

Glad it's all working out for you. It will probably take a couple of weeks of testing and making additions until you work out the addition amount that's right for your pool. Sounds like you're already pretty close!

Janet