Chlorine and pH problems following missing stabilizer

We have an 18,000 gallon pool, in ground with vinyl liner.
Hayward DE filter with a Hayward Super pump.
pH 8.0, chlorine 1.0, water crystal clear.
At the start of the season, we had no chlorine, but normal levels for other tests. When we began shocking the pool however, it became unable to hold any chlorine at all. We were told by a pool store that we needed to reach the chlorine demand and began putting tons of dichlor and trichlor tablets and granules into the pool. Well, not surprisingly, the pH of our pool went so low that the test strips no longer read it, and the stabilizer is at least 150 ppm.
After putting ten pounds of pool store pH up (sodium carbonate) into the pool, the pH was still too low to read, but the alkalinity had risen to 180 ppm. That is when we gave up on pool store chemicals and stumbled upon this website.
We added 17 boxes of Borax, which, thankfully, raised the pH to ~8.0 (admittedly a little high) but either latent effects of the pH up, or (less likely) the Borax, raised the alkalinity to even more obscene levels. We also switched to unstabilized chlorine in the form of bleach (at this point the pool would still not hold chlorine). We did one dose of 2 cups muriatic acid last night to start lowering alkalinity, and thankfully, the pH came back up after aeration as it should, although we're putting off lowering alkalinity for now.
As of today, we added 121 oz 8% bleach at 11:30, which maintained a chlorine of 1 ppm until 3:30, when we added 121 oz more. Hopefully this is a good sign, but bottom line, we just want the pool to hold chlorine the way it should and need to be able to maintain it for the summer.
I will never go to a pool store for guidance again.

I'm glad you got the problems resolved.

What you probably encountered were the after effects of bio-degradation of the your CYA (Stabilizer) over the winter. It can take as little as a week or two of 'slimy' conditions for your CYA to began to degrade.

When that happens, the follow-on chlorine demand will sometimes be very, very high. As you discovered, using dichlor or trichlor to correct is often not ideal.

You'll probably want to take steps to avoid this next winter.

(Welcome to the forum!)

We could not follow up with you until your reply...we still have the chlorine problem. Our pool will only hold a bottle of 8.5% bleach for approximately four hours. The level rises to 3ppm and over the course of four hours drops to 1 ppm.

Our stabilizer remains at 150. Alkalinity is off the chart. PH is 7.8.

The water is clear but we are seeing fine, sandy, light in color debris gathering on the bottom of the deep end. I will vacuum thoroughly tonight.

How should we proceed?

I wonder what your CYA was when you closed?

How are you testing? CYA tests with methods other than the disappearing dot test are not trustworthy.

Regardless:
1. Add 2 gallons of bleach at night. Doing so will gradually consume the chlorine demand, and should gradually oxidize whatever residue you have.
2. Keep the pH high, for now. Low pH tends to result in some pretty nasty chlorine+goo compounds; high pH tends to favor less nasty versions.
3. Do NOT cover your pool. Some of the compounds likely to form are removed by chlorine + solar UV, rather than chlorine alone.
4. If you aren't using the K2006 or an equivalent drops based kit with the DPD-FAS chlorine test, you need to get a K2006.
http://pool9.net/test/
5. If you have any idea what your CH (calcium) level is, say so.
6. ID your filter by make / model.


Unfortunately, cleaning up the remnants of bio-degraded CYA can be an extreme PITA. Good luck.

I will have to look up the filter model number...other than what I already posted...Hayward DE filter...
I am not sure.

CYA was 40 when the pool was closed and was actually brought back to that and fine after our first shock treatments...but when the chlorine wouldn't hold, we were instructed to until add 10 lbs of granular chlorine at a time every so many hours as we tried to get the chlorine to hold at 5 ppm for 24 hrs. Then the CYA went through the roof and chlorine just kept disappearing...along with a ton of money.

Testing with aquacheck strips and took two samples to two different pool stores and all results were the same.

When I put the two bleaches in at night, does it matter what the chlorine drops to the next day?

1. Please post all 3 results you got (2 stores + aquachek)

2. 10# of what kind of granular chlorine?

3. Exactly what chemical was used for your "first shock treatments" . . . and how much?

4. Do you realize that each pound of dichlor granular chlorine (sodium dichloro-isocyanurate, 55% or 61% available chlorine) will add a little more than 3 ppm of stabilizer to your pool. (10 lbs => 30 ppm CYA)?

Aquacheck Between 150-200 but closer in color to 150
RP (Pool Store 1) 40 (prior to VP treatment)
VP (Pool Store 2) 150
RP (Pool Store 1) 150 (returned after VP treatment)

Initial shock was TKO which is sodium hypochlorite
Burned through many bags varying in amount per time...wouldn't hold chlorine. Most bags at once...probably six. Total used over days...probably 14. $5 a bag.

VP had us put in 10# of granular dichlor chlorine (and check every 4 hours...if FC dropped below 5 ppm add another dose)...keep going until at 5 ppm for 24 hours without treatment. 25lbs sold for $99 and we used almost 3 before we lost hope...did nothing...money gone and CYA now sky high. We were desperate to get this cleared up...graduation party in three weeks, so we got sucked right in.

Then we found your website and hope to finally get back on track...even if it means draining and refilling.

Yes, we have come to realize the fatal CYA advice from the second pool store. I have enlisted my daughter's help now...she has been reading many of the posts on your website and applying the chemistry she knows and then explaining it easier terms for me and my husband to understand.

Quote:

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Originally Posted by Cstaines

Aquacheck Between 150-200 but closer in color to 150
RP (Pool Store 1) 40 (prior to VP treatment)
VP (Pool Store 2) 150
RP (Pool Store 1) 150 (returned after VP treatment)

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No idea what your abbreviations are, nor what the numbers are for.

Please report results in some form like this:

FC (free chlorine): store #1 => x.x; store #2 => y.y; Aquachek => z.z
and so on for
pH
TA (total alkalinity)
CH (calcium hardness)
CYA (cyanuric acid).

And . . . do NOT drain your pool. Draining an in-ground vinyl pool typically destroys the liner!

Quote:

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VP had us put in 10# of granular dichlor chlorine (and check every 4 hours...if FC dropped below 5 ppm add another dose)...keep going until at 5 ppm for 24 hours without treatment. 25lbs sold for $99 and we used almost 3 before we lost hope...did nothing...money gone and CYA now sky high.

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Are you saying you've used 3 x 25lb of dichlor?

Sorry. Trying.

Those are CYA readings:

CYA : Aquacheck => between 150 and 200, color closer to 150; store #1 => 150; store #2 = 140

I will get another sample tested tomorrow as the last printout I have from store #2 was prior to the 10 # of Aqua Prep they had me put in the pool to raise the Ph...which put my TA through the roof. I will post those results after I swing by Store #1 at lunch. I really wish I had known about this site sooner.

TC and FC have not been sustained for more than 8 hours on their own above .5 using OTO kit we purchased.

Got it on the CYA; need the other numbers.

And again:

Quote:

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Are you saying you've used 3 x 25lb of dichlor?

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"Store#2 had us put in 10# of granular dichlor chlorine (and check every 4 hours...if FC dropped below 5 ppm add another dose)...keep going until at 5 ppm for 24 hours without treatment. 25lbs sold for $99 and we used almost 3 before we lost hope...did nothing...money gone and CYA now sky high. We were desperate to get this cleared up...graduation party in three weeks, so we got sucked right in."


To answer the dichlor question:

Yes...as instructed by the pool store. They wanted us to keep going too...called it "chlorine demand."
The level would go to shock level...but the longest we could maintain 5ppm or higher was about 7 1/2 hours. It was Carribean Blue Chlorine Guard Granular Shock. They told us they are seeing an increasing number of pools with this problem.

I will send all numbers after lunchtime today.

So how many pounds of dichlor -- in total -- have you added to the pool this season? (please answer with a number!)

What was the condition of the water on opening? (Clear/cloudy; green/blue; slime on sides/no slime, etc)?

Has the water been green, or the sides slimy, at any time SINCE opening?

Pool was very cloudy upon opening. Couldn't see the bottom...but no green or blue cast. We used a product (will have to look at the name when I get home) that is to bind to the organic matter and then it is filtered out. We thought for sure the chlorine depletion was being caused by organic matter. We kept cleaning and shocking and backwashed (twice because the pressure was up and wouldn't bump back down). We could then see the bottom and removed all debris (a few leaves and a pile of earth worms). We have backwashed twice more over the course of the last two weeks to be sure the filter was clean and free of anything that could be depleting the chlorine. Hosed well...looked great. No discoloration of earth or fingers in the filter. Everything appeared normal, but still will NOT hold chlorine levels. Pool has remained crystal clear ever since.

In total, we put 70 lbs of dichlor chlorine into our pool over a 36-48 hour period of time. The second dose of 10# is wiped out my Ph. They gave me the Aqua Prep for that...we were spiraling out of control at this point.

That is when my husband said we are done with this process.

Then is we found this forum. Started treating the Ph with Borax since our TA is now really high from the Aqua Prep. The Ph has been 7.8 for about a week and a half (OTO test and Aquacheck strips).

The pool looks fabulous...you would never guess we were having such problems!

Store # 1 Water tested at 12:00 p.m.

FC .5
TC .5
pH is 8.2
TA is 235
Calcium Hardness is 200
Stabilizer is 135
No Phosphates present

OK.

With 70 lbs of dichlor into an 18,000 gallon pool, your stabilizer level is now well over 200 ppm.

Please do things on the list below, exactly:

1. Test chlorine levels with an OTO /phenol red drops kit. Tell me the color you see. It may not be anything on the test kit block, but may be a different color.

2. Buy a gallon of distilled (DISTILLED, not anything else) water from Walmart. Test your pH using a mix of 2/3 cup of DISTILLED water and 1/3 cup of pool water. Tell me what result you get, and whether it matches the pH test with straight pool water.

3. If you don't have a K2006, or have one on the way, order one today. With a CYA of possibly 300 ppm, you MUST have a K2006 to manage your pool.

4. Your other option, if you won't want to get a K2006 and follow some rather exotic methods this summer (not particularly hard and not expensive, but weird), you need to hire a vinyl liner builder or service guy to drain 4/5 of your pool and then refill. Trying to drain it your self will either (a) destroy your liner or (b) be slow and difficult

You can NOT do it a little at a time! I just did the math, in an iterative spreadsheet: if you drain 25% of the pool each time, you'll have to repeat the process EIGHT times to get down to 40 ppm of stabilizer!

We cross-posted, but the results you posted don't change my recommendations.

Also, if you added 70 lbs of dichlor to an 18K pool, there is NO way your CYA is less than 200 ppm! It is almost certainly more than 300 ppm.

Did the pH test with distilled water and the result was between 7.5 and 7.8

OTO drop test matched this result.

The K 2006 will arrive any day now.

Daughter added more bleach before I got home from work. How long should I wait before testing? Also just had a really hard rain and it is still raining moderately now.

You can wait.

With CYA > 200 ppm, an appropriate chlorine level is going to be in the orange tinted range (chlorine > 20 ppm).

Right now, you just want to avoid algae, while waiting for the kit, and good data. As long as the pool is algae free, you can swim. I wouldn't recommend wearing a new $100 swimsuit when you do, however.

However, watch out for eye and skin irritation: swim 10 minutes for the first time, and then wait and see. Sometimes, by products of CYA loss can combine with chlorine to form some irritating chemicals, and you don't want to spend 2 hours in the pool, and then pop-up with 'hives' 2 hours after you get out. (It's not a real allergy, but it feels like one!)

I just received the K2006 pool test kit. We are ready to follow the next instructions.

Watch the videos, here:

http://pool9.net/tk-guide/
http://pool9.net/tk-interfere/

Notice particularly the TA interference video. Then:

1. Test the chlorine levels, using the 10 ml sample and the 0.5 ppm/drop test.
2. Mix 1/4 cup of pool water with 1/2 cup of tap water. Test for CYA. Multiply the result x3
3. Report those results, including FC (free chlorine) and CC (combined chlorine) Tell us what you water looks and smells like (if there's an odor).

4. Make sure you have a gallon of distilled water from Walmart on hand. Mix 1/4 cup of pool water with 1/2 cup of DISTILLED water. Test the pH of this sample. The result is as tested; no multiplier.
5. Test TA, adapting for high chlorine.
6. Test CH
7. Report those results. Tell us what you water looks and smells like (if there's an odor).

Alright, just tested everything.

Water is clear with a very faint chlorine smell
Free chlorine 10.5 ppm
Combined chlorine 1.5 ppm
Cyanuric acid 300 ppm
pH 7.6
Alkalinity 320 ppm
Calcium Hardness 220 ppm

Use muriatic acid to lower your pH to near 7.0, and just keep it there.
http://pool9.net/ma/

If you can aerate, that will not only help lower the TA, but will help remove some of the combined chlorine compounds that are forming.

Also, you need to add 6 gallon doses of PLAIN 8% bleach, each evening. With CYA = 300 ppm, a *normal* chlorine level is 15 ppm; 'shock' is 30 ppm or more. You'll need to get the chlorine level up above 20 ppm. Be sure to use the 10ml test sample with the K2006 (each drop = 0.5 ppm). Otherwise you'll use up your chlorine test drops too fast.

You might hold the record for the highest CYA award. I can't remember another pool that we have had on here recently with a CYA level that high! Thank you, pool store!!

That sounds good. A question though, if the chlorine is well above 20 ppm in the evening, will we still have to add the 6 gallons of bleach that day?

How much more chlorine you'll need to add, depends entirely on how much partially degraded CYA goo is left.

You can run a chlorine demand test to find you, if you like: http://pool9.net/bucket-demand/

Working on lowering the pH...about half way there. Getting some pretty foam with the aeration though. Should we be concerned about that? Chlorine seems to be holding high really well. Will try to fit a demand test in. Was still 27 ppm this morning.

Is it ok to start using our heater?

Is it ok to cover, or will the high chlorine eat the new solar cover?

Last, we were thinking about trying to start chipping away at the CYA with a 25% drain. We realize this will not have a profound immediate effect...but if we never start moving toward a healthier level, we may never get there. I would consider a larger drain, but I don't feel our pool could withstand it as we have a lot of ground water in our yard. I have yet to find an expert in this area of Pennsylvania who could help us. Thoughts?

Quote:

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Originally Posted by Cstaines

Getting some pretty foam with the aeration though. Should we be concerned about that?

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It probably indicates some remaining unoxidized 'goo'; while this is the case, your water may be unpleasant to swim in. The solution to most of these issues is sustained high chlorine + sunlight.

Quote:

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Is it ok to start using our heater?

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Not with these numbers:

Quote:

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pH 7.6
Alkalinity 320 ppm
Calcium Hardness 220 ppm

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You'll scale up the inside of your heater core badly.

Quote:

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Is it ok to cover, or will the high chlorine eat the new solar cover?

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No, you need the sunlight, to help break down the 'goo'. It won't hurt the pool to cover at night, or on rainy days. BUT, as that 'goo' is oxidized, it will tend to form volatile chlorinated by-products. These will evaporate . . . OR accumulated under the cover, if the pool is covered. These sorts of gases CAN damage plastics.

Quote:

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Last, we were thinking about trying to start chipping away at the CYA with a 25% drain.
I would consider a larger drain, but I don't feel our pool could withstand it as we have a lot of ground water in our yard.

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I think you don't realize how many times you'd have to drain 1/4 of the pool in order to have an effect. The chart below shows the steps it would take to get below 300 ppm, draining in increments of 10% up to 25%:

https://lh3.googleusercontent.com/-o...%2520steps.jpg

However, if you want to go ahead and try, FIRST dig a post hole on the LOW side of the pool, as close to the pool as you can get. Dig it 1 foot deeper than you intend to drain the pool. (ie, drain 1ft; dig 2ft hole). Cover the hole and wait 24 hours. If it's dry, you're relatively safe. If not, don't!

Keep in mind that this does NOT guarantee that you won't damage your liner by draining!

Ok...you guys are obviously thinkers and willing to think outside the box.

My husband and I were trying to come up with a way to drain the existing water while adding new water in order to maintain pressure on the liner (walls). Would it be possible to place a large winter cover on top of the existing water, keeping the syphon underneath of it...start adding water to the top while syphoning water from the bottom?

What numbers would be acceptable to run the heater?

I am really trying to remain optimistic about this whole thing, but I have to be honest, it is all very overwhelming. We have a graduation party at our house in two weeks. Crappy cold water that nobody can (or would want to) swim in. The college tuition payments have already started and money is becoming an issue. We have depleted two Walmart bleach supplies (perhaps that is another award we can hold along with the highest CYA ever). I do realize how many drains this will take, but if we don't drain, when will it ever get better??? When will we be able to enjoy he pool instead of just look at it?

I can walk you through the process of managing a HiC2 pool -- high CYA & high chlorine. It shouldn't cost any more (and may cost less) than running in the ordinary way.

There is very little I can do in the way of a quick fix:
+ you can not safely drain and refill your pool, without hiring a professional to set up suction to hold the liner in place while the pool is drained.
+ even then, you can not drain your pool now, because the ground is wet.
+ you can do a 'drain in place' but you'll need a winter cover that is 15 - 20 feet wider AND longer than your pool. It will probably take a week, and when your done, the water temp will be whatever your fill water's temp currently is -- probably colder than it is now.
+ without knowing your fill water's condition, I have no idea what your TA and CH would be at that point, but currently those levels are too high for a heater.
+ there is a way to 'warm' the pool a little (3 - 4 degrees) assuming your current liner is light colored, by laying a large piece of black plastic on the bottom.

There is an option you could consider. Solar covers aren't that expensive -- certainly less than the cost of 2 weeks gas heat on a cold pool. If you're willing to sacrifice the cover, you could lower the pH some, keep the chlorine high, and begin aerating. Doing this would allow you to strip BOTH excess TA and the volatile oxidation products that are forming. It might damage your cover -- or it might not.

You'd need to order this fitting (after verifying that you can fit it into an existing return socket):
http://www.amazon.com/exec/obidos/AS...2/scouscho-20/
Using this fitting would allow to rapidly and effectively aerate your pool, even with the cover in place.