How do you deal with bleach breakdown?

[Tekcor]

For the past ten years I’ve been using 12.5% bleach for sanitization, but I’ve been mostly in the dark about levels. I know you’ll hate to read it, but I’d balance everything at the start of the season using the local store’s WaterLink SpinTouch tester, then just wing it on chlorine for the rest of the season. I’d get into a rhythm of just sort of knowing when and how much to add based on water look and smell. I know, bad.

So I’m doing better. I got the Taylor 2006C to keep a better eye on things. I’ve had to shock (long story, don’t worry about) and was told by PoolMath to add 2 gallons of 12.5% to bring FC up to 12, the shock level for my 30 CYA. I have more CYA going in now to bring that up to 45 too. Opening the bottles, I’m just not hit with that bleach smell that I expect to be, so on a hunch I added 4 gallons instead. After waiting an hour, tested again, and got 15 FC. If this was really 12.5%, it would be more than 15 I’d think.

I know chlorine breaks down. I’ll have to check the date in the morning, but I think the stuff I’m buying from Ocean State is cheap because it’s old.

So I’m trying to figure out what to do. I’d rather not use a sanitizer that I have to worry about when it was manufactured, but Cal Hypo, Trichlor, and Dichlor all have side effects. So I either deal with having to find good bleach, continuously upping my CYA, or continuously upping my calcium. Salt isn’t really an option.

How do you guys deal with this? All the sanitization options kind of suck. I mean, this isn’t exactly new, I’ve been at this a while. But I’m just now noticing the extreme effects of aged bleach.

 

[Bperry]

For the past ten years I’ve been using 12.5% bleach for sanitization, but I’ve been mostly in the dark about levels. I know you’ll hate to read it, but I’d balance everything at the start of the season using the local store’s WaterLink SpinTouch tester, then just wing it on chlorine for the rest of the season. I’d get into a rhythm of just sort of knowing when and how much to add based on water look and smell. I know, bad.

So I’m doing better. I got the Taylor 2006C to keep a better eye on things. I’ve had to shock (long story, don’t worry about) and was told by PoolMath to add 2 gallons of 12.5% to bring FC up to 12, the shock level for my 30 CYA. I have more CYA going in now to bring that up to 45 too. Opening the bottles, I’m just not hit with that bleach smell that I expect to be, so on a hunch I added 4 gallons instead. After waiting an hour, tested again, and got 15 FC. If this was really 12.5%, it would be more than 15 I’d think.

I know chlorine breaks down. I’ll have to check the date in the morning, but I think the stuff I’m buying from Ocean State is cheap because it’s old.

So I’m trying to figure out what to do. I’d rather not use a sanitizer that I have to worry about when it was manufactured, but Cal Hypo, Trichlor, and Dichlor all have side effects. So I either deal with having to find good bleach, continuously upping my CYA, or continuously upping my calcium. Salt isn’t really an option.

How do you guys deal with this? All the sanitization options kind of suck. I mean, this isn’t exactly new, I’ve been at this a while. But I’m just now noticing the extreme effects of aged bleach.

Without test results it’s hard to advise. If your chlorine was too low, you may have something growing and eating the chlorine. Post up some results.

The salt water chlorine generator is always generating fresh FC. Might be an option to consider.

 

[V___25]

In the effects of adding section of poolmath, how much does it say your FC should increase by for your pool? For my pool, adding 4 gallons of 10% increases by 17.
4 gallons of 12.5% should raise it by 21.

How are you storing your chlorine? Are you stocking up and storing large amounts at home? I buy my LC at WalMart and those jerks will soon take down the pool stuff for Halloween and fall stuff so I have to store enough to get me through the end of the season. I find I get better shelf life if I store it in the basement rather than outside in the pool box. Definitely check your dates though - plenty of times stores will put out stuff from last season even. I found stuff at Ollies at the start of this year that was from 2021.

I don't mind using LC but why is a SWG not really an option for you? Just the cost?

 

[Tekcor]

In the effects of adding section of poolmath, how much does it say your FC should increase by for your pool? For my pool, adding 4 gallons of 10% increases by 17.
4 gallons of 12.5% should raise it by 21.

How are you storing your chlorine? Are you stocking up and storing large amounts at home? I buy my LC at WalMart and those jerks will soon take down the pool stuff for Halloween and fall stuff so I have to store enough to get me through the end of the season. I find I get better shelf life if I store it in the basement rather than outside in the pool box. Definitely check your dates though - plenty of times stores will put out stuff from last season even. I found stuff at Ollies at the start of this year that was from 2021.

I don't mind using LC but why is a SWG not really an option for you? Just the cost?

Yeah, cost. The way the plumbing was setup, there’s no logical way to fit additional equipment. It’d pretty much need to be done over. So the initial cost of the equipment itself plus the labor to rework the plumbing, means it’s not really viable. Oh and electrical too. I only have a single outlet for the pump on a 120V 20A circuit. So… labor for that. Not sure what a SWG would need for power, it might not “fit” into a circuit with a (up to) 1700W pump.

As for storage, no I’m not stocking up. They stay in my insulated garage, and I try not to keep more than I would need for the next week or two.

 

[PoolStored]

Know what you are buying, store in a cool place:

Chlorine Date Code Decoder - Further Reading

www.troublefreepool.com

Breakdown of Bleach Over Time by Storage Temp - Further Reading

www.troublefreepool.com

 

[Tekcor]

Just got around to checking the date. 22206. So July 24th. We'll call that three weeks. It's been pretty warm, so although I think it's been closer to 80F in the garage, let's call it 90F for the sake of argument. That should be 9.1% according to the chart. Of course, I have no idea what temp it was during transport, but it probably wasn't pleasant in the back of a trailer. At that concentration in 22k gallons, PoolMath says 18ppm. A difference in 3ppm is outside of margin of error, but it's also not THAT bad either. I just tested again this morning and got 14.5ppm. Tested CYA as well, but it doesn't look like much had dissolved overnight, which isn't surprising as this stuff is slow. But I hate Taylor's CYA test anyway. It's far too subjective. I won't have a number until more of it dissolves, but even then, I have a feeling I'll still be able to see that black dot.

Anyway, the chemistry itself isn't really something I need help with. It's not that hard and I have enough experience to understand what's going on. I'm just looking for input on what people are doing with their bleach. But it sounds like I don't really have the breakdown problem I thought I had. 4 gallons of 12.5% is $18 at Ocean State Job Lot. Or 3 gallons of 7.5% (IIRC) at BJ's for $15. Even with losing a few percent from the Ocean State stuff, it's still more cost effective than BJ's.

 

[Getitrite]

I've used 12.5% Austin's Pool Tech Shock from BJ's for the past 3 years and I have had very good luck with it. (Although, this year the price here went up to $19.99, case of 4 gal.) I started the season with 8 gallons left over from last year (21175). Just for grins, I entered 10% into PoolMath to open the pool. Dead on B@11s Accurate! (That's an industry term...) Off-season storage was in a basement storage area, temp about 65. Based on other threads commenting on loss of strength, I consider myself lucky. (Or I've underestimated my volume? But my tests seem to confirm.) YMMV.

 

[Tekcor]

Oh your BJ's has the Austin shock? Mine just has 3 gallon packs of 6 or 7.5%, I can't remember which, for $15. The Ocean State Job Lot has the Austin 12.5%, as well as Diamond Chemical Company 12.5%, both for $19.99. The devil is in the details. Every box of the Diamond had a date of June 8th, and they don't even follow the standard format. They write it as MMDDYY. The Austin has 22 207, aka July 26th. Gee, I wonder which I should buy? /s. And before somebody points out that 060822 could be August 6th, it's a New Jersey company so the date is probably American. I confirmed at home, as I found an old empty bottle that never made it into the trash that has 042621 on it.

I think all these bottles are probably the worst part of using bleach... That and the guesswork I suppose.

 

[Getitrite]

I think all these bottles are probably the worst part of using bleach... That and the guesswork I suppose.

That's one reason I bought SWCG for this season. Working REAL WELL for me! PoolMath has handled the guesswork for me. I trust it; Calculate-Dose-Verify the Dose. I don't get more precise than that.

 

[Tekcor]

Yeah that might be part of a longer term project. My pump can use up to 15.6A of my 20A circuit. That doesn't leave much room for a SWG. So long term, I might have a shed added nearby, get a subpanel there, and run new electrical from that to the pool.