Chlorine Lock ????

[CarlD]

P-R:

I really appreciate that sometimes you make a business decision for its long-term impact. A family-owned pool store working SO hard for you is one you want to give business to. I'd do the same--in fact, I do give biz to one store that has higher prices because they EARN it with the help they've given me over the years.


The pool chem company's chemist is going to recommend company-sanctioned options--like buying cal-hypo.

You CAN use it--I'm sorry if I was unclear--but I'm not a fan of it. Water can be cloudy until it dissolves, and, if hardness goes too high can also make it cloudy. Cal-Hypo can also drive up pH.

If you now have your test kit, test your Calcium Hardness (or just Hardness) and your total Alk. (I think your T/A is 100--"99" is a meaningless #) If your hardness stays under 500ppm and your T/A is 100 your water should stay clear once it dissolves in.

I'm trying to figure out why they prefer it--and all I can think of is that since it takes time to dissolve they are thinking you'll have a residual chlorine level in your water longer.

But I still would go with LC--the amount you figure to add is:
1 gallon of LC (12.5%) will add 12.ppm of FC to 10,000 gallons of water. So it takes 3 1/3 gallons to get that in your pool...Ballpark is that 4 1/3 gallons gets you to about 15ppm--so might as well make it 5 gallons.

You are DEFINITELY fighting something but now your FC is 1 and your CC is 1 so it's getting there.

I don't know of a better way. The ONLY thing I can think to do is a newer, more intense version of our method, which is do-able on a weekend. But you MUST have the FAS-DPD test to do it. That's to have many, many carboys of LC--like 5 or 6. Add one in the morning and test the water 1/2 later. If the FC isn't at shock
level, add more LC. Do this every half hour until FC reads at shock level and continue measuring it and adding LC whenever it drops off. The idea is to NEVER let the FC drop below the killing level to absorb what ever is in your pool.

There MUST be some contaminant--either that or you've got some really nasty and resistant to chlorine bacteria growing in there. Something's there that ordinary tests don't show--and I don't think it's phosphates either--and we know it's not ammonia, but must be something similar that's not "living"--like bromine.

You may want to consider a full water replacement--Poconos has a method that doesn't risk damaging your liner--involving a huge sheet of plastic--you add new water on top and drain the old from below and there's always pressure on the liner.

Unless you are willing to keep up the LC regimen, I must admit I'm coming to the end of my ideas.

Chem_Geek, Waterbear, Mods, Marie? have you got any other ideas?

[poolrescue30]

The water was tested for phosphates a week ago and there wasn't any in the pool.
I tested this morning at 9am and the FC was .25 and the CC was .25, using the FAS-DPD kit. I can only hope that it's a sign I (we) are getting rid of the contaminant. But the FC is being used at a really high rate to get rid of the TCL, so maybe it was ammonia as chem-geek had said. I will not use calcium hypo as their suggestion as the pool is cloudy, I wil try the LC regimen you suggested starting Sunday morning , my day off !!
You want me to test every half hour ?? Is that sufficient time for the first 5 gallons to get around ?? And then I will top off as you suggested. At this point I am also contemplating removing half the water, which would still keep the liner in place and replacing with clean water, my only question is will this dilute the contaminant enough to then be able to kill it with a "normal" chlorine maintnenace program ?? Your help is really appreciated.

[CarlD]

How did you measure .25? Using the standard Taylor FAS-DPD test you can only measure .5 (when you use 10 ml of water) or .2 (when you use 25ml of water). Do you have the Taylor FAS-DPD test? Drop tests are titration tests--you go till the color changes and it's either one value or the next. For example, your FC level cannot be .25 with the Taylor test. It can be 0, .2 or .5, or any multiple of .2 or .5 (.4, .6, 1, 1.2, 1.5, etc.)

How are you conducting your own FC/CC test? This concerns me.
Are you adding DPD powder until it turns red, then counting drops from the brown bottle, 1 drop being either .5 or .2ppm until it goes completely clear? ( set it on the white label to make sure I've gotten out the last tinge of pink)

Are you then, adding to that same solution 5 drops from Reagent 0003?
Is it turning pink or red again?
How many drops does it take to make it go clear?

I've not tried the 30 minute drill--it's new to me, but I'm trying very hard to get you over the hump of fighting the contaminant and back to maintaining a normal pool--and your regimen should have made it clear by now....so either something else is going on in your water or I'm not communicating correctly or completely with you.

[poolrescue30]

My mistake, it took 2 drops of 871 to turn it clear and then after the 5 drops of 0003 it turned pink and took 2 drops to turn clear again. So it would be multiplied by .5 , I divided by mistake. The FAS-DPD kit is from TFP. As per the pool store test just now , there is 0.0 FCL and 0.5 CC ,there was .1 FCL and .6 CC yesterday. Does this mean we are on the way down ?? As far as TA it's 105 and Hardness is 170. It does look like we are heading down , but the FCL has been being used up very quickly ? Thanks

[chem geek]

Chem_Geek, Waterbear, Mods, Marie? have you got any other ideas?

Carl,

For some reason, there's been quite a few reports of unusual chlorine demand on multiple forums. Some of them have clearly been ammonia issues and most of them got cleared up with the demand going away once the ammonia and resulting combined chlorine (after adding chlorine) were eliminated. A few have persisted with continued chlorine demand and I, too, am at my wits end to know why.

It does not appear to be nascent algae growth as phosphate levels are nil and the water is clear in these cases (and bucket tests don't show algae blooming). In one case, the chlorine loss is only during the day so appears to be something like bromine, but the loss was quite rapid -- faster than one would expect with bromine and it was verified that there was CYA in the water.

One obvious thing would be to make sure that the skimmer and filter are cleaned out since lots of small organics (such as pollen) would create a high chlorine demand. In theory, one would only see such demand during running of the pump.

I think your recommendation of a concentrated chlorinating liquid effort on a frequent basis is reasonable. I would, however, like to know with some certainty whether the FC loss in this case occurs primarily during the day or if it also occurs overnight. Also, if chlorine gets added and the FC drops very quickly, CC then goes up, and then CC goes down in about an hour or so, then that would likely be oxidation of ammonia (though I don't know why it wouldn't show higher in an ammonia test). Also, it seems like we've only got some pool store numbers for things like CYA -- it would obviously be much better to confirm the water chemistry parameters with a known good test kit such as the Taylor K-2006 or the TF100.

Richard

[CarlD]

My mistake, it took 2 drops of 871 to turn it clear and then after the 5 drops of 0003 it turned pink and took 2 drops to turn clear again. So it would be multiplied by .5 , I divided by mistake. The FAS-DPD kit is from TFP. As per the pool store test just now , there is 0.0 FCL and 0.5 CC ,there was .1 FCL and .6 CC yesterday. Does this mean we are on the way down ?? As far as TA it's 105 and Hardness is 170. It does look like we are heading down , but the FCL has been being used up very quickly ? Thanks

Well, if you measured 10 ml of water, and use 2 drops of 871 to clear it, your FC is 1.0.
If you then added 5 drops of 0003 and needed 2 more drops of 871 to clear it your CC is also 1.0
And your TC is 2.0

Now that you have your TF-100, don't bother with the pool store testing--it will just cloud ( ) the issue. TA and Hardness are fine for now--ignore them.

[CarlD]

Carl,

For some reason, there's been quite a few reports of unusual chlorine demand on multiple forums. Some of them have clearly been ammonia issues and most of them got cleared up with the demand going away once the ammonia and resulting combined chlorine (after adding chlorine) were eliminated. A few have persisted with continued chlorine demand and I, too, am at my wits end to know why.

It does not appear to be nascent algae growth as phosphate levels are nil and the water is clear in these cases (and bucket tests don't show algae blooming). In one case, the chlorine loss is only during the day so appears to be something like bromine, but the loss was quite rapid -- faster than one would expect with bromine and it was verified that there was CYA in the water.

One obvious thing would be to make sure that the skimmer and filter are cleaned out since lots of small organics (such as pollen) would create a high chlorine demand. In theory, one would only see such demand during running of the pump.

I think your recommendation of a concentrated chlorinating liquid effort on a frequent basis is reasonable. I would, however, like to know with some certainty whether the FC loss in this case occurs primarily during the day or if it also occurs overnight. Also, if chlorine gets added and the FC drops very quickly, CC then goes up, and then CC goes down in about an hour or so, then that would likely be oxidation of ammonia (though I don't know why it wouldn't show higher in an ammonia test). Also, it seems like we've only got some pool store numbers for things like CYA -- it would obviously be much better to confirm the water chemistry parameters with a known good test kit such as the Taylor K-2006 or the TF100.

Richard

As usual, Richard's advice is excellent. My own chlorine usage has been much higher this summer than usual. I'm putting in 2 quarts of 12.5% every day--about twice as much as I usually use. Not showing CC levels, but it's just using it up. I'm now looking at boosting my CYA level and running a higher residual.

The ONLY thing I can think of is that I've not been covering my pool as much as it's been warm, so....I think there's been gassing off by aeration to raise my pH (which has also been higher than usual, tho still in the 7.5-7.8 range) and that my chlorine hasn't been as effective and is getting consumed...at least that's how my logic is running.

So... I've filled a floater with Tri-Chlor (Gasp!) to try to keep pH down, raise CYA up a bit, and keep a steadier flow of chlorine into the water. Of course, I'll be watching my numbers like a hawk....

[shadowman]

So... I've filled a floater with Tri-Chlor (Gasp!) to try to keep pH down, raise CYA up a bit, and keep a steadier flow of chlorine into the water. Of course, I'll be watching my numbers like a hawk....

I mentioned this to you in another thread so I can't help but chime in. I had been using huge amounts of LC to rid myself of mustard algae and to maintain a higher than normal level to ward it off. I too used my floater (another gasp) to raise my CYA and make sure my chlorine didn't drop while I was off camping. I took it out when I came back Sunday and haven't had to add chlorine in four days. I do keep the blanket on all the time to save water. My water is extremely snappy right now and I am testing every day and keeping my fingers crossed that it will stay that way.

[poolrescue30]

I did put in the 15 lbs of calcium hypo shock Friday at 7:00 pm, I know Carl you said chlorine is chlorine, but this was the advice of the pool store's chemical supplier who also produces his LC. I tested the water tonight at 11:00pm and it shows .5 FCL and .5 CC, I don't know if we are getting anywhere ??? I will take a sample to test by the pool store and we are also sending a sample to the chemical supplier as well. I'm at my wits end and don't know if I should just drain the pool halfway, or the whole damn thing OR do we just continue with a clean ,clear (when the calcium goes down ) algae free pool, with a CC problem and treat it with some bleach every couple of days and swim as nothing happened ???

[CarlD]

I'd like to see the pool store's test results, see if they confirm yours. I'd also like you to get test strips (Hach or Lamotte only) and see if they confirm it too. Normally I don't recommend strips, but I want to see if all 3 testing methods (You with drops, the pool store, and the strips) are all consistent with each other.