Huge Chlorine Demand Post Conversion

[Stillini]

Hi Guys,

So we converted at the beginning of the season and we are still struggling with a huge chlorine demand. We have been using 15 gallons of 12.5% (5 gallons every 4 hours), then I tried 6 bags of BurnOut Shock (every 4 hours). We have been doing it for days and it's costing me tons. I've tried it during the day, at night. It just wont hold. As of this weekend, I am just adding a gallon of 10% liquid and then doing 6 bags at night. It goes up to 18PPM but then it's back down to .3 to .5 in the morning. Water is crystal clear. Any thoughts?

 

[YippeeSkippy]

hmmmmm? how are you testing your water? Which test kit? Are you using PoolMath to guide your additions?

Can you look at all your nooks and crannies, behind the weir door, the ladder, etc for hidden algae? That could be one explanation?
Can you provide us with a full set of test results:
FC
CC
pH
TA
CH
CYA
Salt if applocable

Also, please write out a signature line describing your pool, its equipment, how you chlorinate and test, so we have that info.

Create Your Signature - Further Reading

www.troublefreepool.com

Maddie

 

[Stillini]

No algae anywhere for sure. Using the TF-Pro kit. Numbers are as follows:

FC: .2
CC: .2
PH: 7.4
TA: 115
CH: 179
CYA: 40
Salt: N/A

19,500 Gallons, Vinyl Pool

 

[kul]

When you say you converted your pool, what do you mean? Did you switch to a SWG?

Edit—— a Baquicil conversion. Sorry. I missed it.

 

[YippeeSkippy]

Ok, next time you add chlorine to the water- please do a FC test again 30 minutes later after the pump has worked to mix it up. See if you met your goal level?

 

[mgtfp]

When you say that you converted to chlorine: How did you conclude that the conversion was completed? Did you ever get your FC to hold? Is it possible that your conversion simply isn't done yet?

Anything else that you added to the pool? Do you have an ingredient list of this Burnout stuff?

I'd recommend to stick with liquid chlorine. To start with, granular forms of chlorine add either CYA or calcium to your pool. And then there is stuff around, marketed to clear green pools, that adds all other sorts of stuff to your pool.

 

[Stillini]

Ok, next time you add chlorine to the water- please do a FC test again 30 minutes later after the pump has worked to mix it up. See if you met your goal level?

Ok...checked twice, I put in a gallon - should raise it to 5ppm. It was at 2.5-3 within 30 minutes

 

[Stillini]

When you say that you converted to chlorine: How did you conclude that the conversion was completed? Did you ever get your FC to hold? Is it possible that your conversion simply isn't done yet?

Anything else that you added to the pool? Do you have an ingredient list of this Burnout stuff?

I'd recommend to stick with liquid chlorine. To start with, granular forms of chlorine add either CYA or calcium to your pool. And then there is stuff around, marketed to clear green pools, that adds all other sorts of stuff to your pool.

1) Now that you are mentioning it, it might be possible the conversion isn't done yet...we just stopped getting the gross baqua goo in the filter and the water was crystal clear. It's been 2 months though.
2) Nothing else added. I've added PH increaser occasionally. Burnout is 100% Calcium Hypochlorite
3) I am 100% going back to liquid only, its just I've just been going through so many bottles I was concerned my garbage people might think I was covering up a crime scene LOL

 

[mgtfp]

Have you ever ever been able to hold FC?

 

[Stillini]

Nothing over .4 really lasts overnight.

 

[mickey4paws]

What kind of filter do you have? I remember when we did the conversation from Baquacil, after the conversion was done, we changed the sand in our filter. It was the worst looking sand, it almost looked like a big piece of plastic.

 

[Mdragger88]

Did you follow this process?

Convert Your Baqua Pool to Chlorine

This Step-by-step guide will help you transform your pool from Biguanide (Baquacil, SoftSwim hereafter referred to as Baqua) to chlorine. Read more

www.troublefreepool.com

Did you exchange any water prior to starting the conversion?
If you had alot of cdx in the water you may now be fighting bromide/bromine. The chlorine you add gets turned into bromine.
Bromine is not protected from the sun by cya. You cannot differentiate between bromine & chlorine on the fas/dpd or oto tests.
Here’s more about the cdx problem in this post
Post in thread 'If I'm going to convert in the spring, would it be best to stop adding anymore CDX? Or doesn't it really make much difference by next year?'
If I'm going to convert in the spring, would it be best to stop adding anymore CDX? Or doesn't it really make much difference by next year?

 

[Stillini]

What kind of filter do you have? I remember when we did the conversation from Baquacil, after the conversion was done, we changed the sand in our filter. It was the worst looking sand, it almost looked like a big piece of plastic.

DE. The baqua goo was gross.

 

[Stillini]

Did you follow this process?

Convert Your Baqua Pool to Chlorine

This Step-by-step guide will help you transform your pool from Biguanide (Baquacil, SoftSwim hereafter referred to as Baqua) to chlorine. Read more

www.troublefreepool.com

Did you exchange any water prior to starting the conversion?
If you had alot of cdx in the water you may now be fighting bromide/bromine. The chlorine you add gets turned into bromine.
Bromine is not protected from the sun by cya. You cannot differentiate between bromine & chlorine on the fas/dpd or oto tests.
Here’s more about the cdx problem in this post
Post in thread 'If I'm going to convert in the spring, would it be best to stop adding anymore CDX? Or doesn't it really make much difference by next year?'
If I'm going to convert in the spring, would it be best to stop adding anymore CDX? Or doesn't it really make much difference by next year?

Followed the process, the chlorine never really held. Have been dumping in tons since. We did use the CDX. Discontinued use after the fall but the pools been a baqua pool for 20 years - previous homeowner used. Water exchange really wasn't an option since we are on a well. How would I test for bromine/what does that mean in terms of getting this resolved?

 

[Mdragger88]

Followed the process, the chlorine never really held. Have been dumping in tons since. We did use the CDX. Discontinued use after the fall but the pools been a baqua pool for 20 years - previous homeowner used. Water exchange really wasn't an option since we are on a well. How would I test for bromine/what does that mean in terms of getting this resolved?

You jumped the gun & should not have added cya until the fc was holding.
You cannot differentiate between bromine & chlorine when testing. The fact that it depletes so rapidly with the presence of cya is a clue that it’s bromine.
The answer is to exchange water to reduce the level of bromine/bromide. Any reduction will help. Small drains & refills use more water in the long run because you’re mixing & diluting each time.
It can take a long time for the bromide to go away as you have seen. The more you have the longer it takes. How many gallons is your pool?

Draining - Further Reading

www.google.com

 

[Stillini]

19,500 gallons

 

[Mdragger88]

Have you done an
Overnight Chlorine Loss Test ?
I would do that first at target fc levels.
If it’s not holding over night you’ve got an organics problem. If it holds overnight but rapidly depletes during the day light hours you might assume you have a bromine issue that necessitates a water exchange. If you use a small pump & refill slowly it shouldn’t put too much strain on your well.
Otherwise you may look at having water brought in.

 

[mgtfp]

Have read through this thread, this pretty much sums up what you are dealing with with:

Baqua to Chlorine conversion with cya of 40.

I have a 14600g above ground pool with a 250lb Hayward sand filter. The water currently has a cya level of 40. I want to convert to chlorine, but I am concerned about the cya in the pool. I haven't added any baquacil/cdx since October of last year. Not sure why my cya is at the level it is, but...

www.troublefreepool.com

In post #100 and following, Matt explains what's going on:

The primary ingredient in CDX is an adjunct sanitizer that contains bromine. Your pool water is likely contaminated with a lot of spent bromide ion (Br-). When you add chlorine to the pool, the bromide gets oxidized to sanitizing bromine … great! … but unlike chlorine, bromine can not be stabilized by CYA against UV loss. So what you basically have is a pool with an unstabilized sanitizer in it. The UV light from the sun is essentially eating up all the sanitizer. You test kit is seeing the sanitizer (because both bromine and chlorine are detected by DPD), but the it’s half life from UV loss is about 40mins or so.

Sorry, but this is why Baquacil in general, and CDX in particular, is such a nightmare to deal with. Your only realistic option tMia to exchange drain the pool and get rid of as much of the contaminated water as possible. Either that, or your just going to have to ride it out with high chlorine consumption until you close the pool and you can drain it and refill it with winter precipitation.

 

[Stillini]

So I haven't been able to get the overnight test done since I haven't gotten to the water before the sun but I did 6 gallons of liquid choline last night around 9PM. I checked it around 2AM and it was at 18ppm. Just tested this morning around 10:30AM. I am under 1 again. Couple of questions/thoughts:

1) What effect does the CYA have on this?

2) I went to the local pool store, requested tests just to see what they thought. .3 on chlorine, no bromine (or bromide - not 100% which one they looked for) and interestingly enough - Softswim B at 17 which is BioGuard's biguanide sanitizer system. Softswim B is the sanitizer portion. We actually also got on the phone with the manufacturer on my issue and they basically stated to just keep doing what I have been doing with "triple shock" until breaks. Their definition of triple shock for my pool is 6 gallons liquid chorine.

I guess my question is, if I keep going this route - triple shock at night (or maybe every other night to keep costs down) Do you think it would eventually work? Or is the only solution draining? Reason I am considering is since it's already end of July, I probably only have 5 more weeks of useful pool time. Appreciate the advise!

 

[Mdragger88]

6 gallons of 10% liquid chlorine will raise your fc 31ppm.
It is not recommended to go above slam level fc for your cya as it risks damage to your liner & equipment.
It is safe to swim with fc anywhere between min & slam level for your cya so long as you can see the bottom of the pool for swimmer safety.
FC/CYA Levels

As far as the cya goes it protects chlorine from the sun. It doesn’t have this effect on bromine so it gets depleted rapidly by the sun.
A true oclt would help you determine if you’re also dealing with organics. Testing after your final night addition to confirm where you stand & again before the sun comes up. Its hard to know if that’s the case the way you did it.
Cya also reacts in some way with the conversion process which is why you’re not supposed to add cya until the fc starts holding. This may simply be because of the moderation effect cya has on active chlorine. Hopefully @Leebo or @JoyfulNoise can elaborate more on that.
As far as I am aware there is no way for the differentiation of bromine & chlorine when testing at home or at the pool store.
From what I can see you have 2 options:
Do the SLAM Process as the water is now which will likely use large amounts of liquid chlorine.
Or replace some/most of the water then do the
SLAM Process which should use less liquid chlorine overall.

Both of these options will eventually overcome any organics as well as bromine present in the water. Neither will be quick. But the more water you replace the easier it should be.