How Chlorine works.....for newbies

[duraleigh]

Frequently, I see threads from newbies that flounder because they do not have a clear understanding of how Chlorine works in their pool.

Chlorine is consumed.....constantly. It will NEVER stay in your pool at a constant level.

It is consumed by organics in your pool....the more organics you have in your pool, visible or not, the more quickly it is consumed. It may be leaves, sticks, suntan oil, pee, and most importantly, algae but the more of these you have in your pool, the more Cl you will use.

If you are just opening and your pool is green with algae, it is VERY likely that a Cl level of 10-20ppm will be consumed overnite.....resulting in a 0 reading the next AM. Even after your pool is crystal clear, you will consume Cl on a daily basis.

If you have water that is not clear, chlorine, and lots of it, will be the answer the vast majority of the time. It will take multiple doses of large amounts of chlorine to clear a very nasty pool.

Secondly, Chlorine is consumed extremely quickly by the Sun. Unprotected chlorine will be consumed by sunlight in a matter of hours.....leaving your pool unsanitized. However, you can protect the Cl from the Sun, to an extent, by putting Stabilizer (CYA, Cyanuric Acid) in your pool. Every successful pool will have stabilizer added in some form to minimize the loss of Cl to the Sun and allow it (Cl) to do it's job working on the organics.

Because of the sometimes overwhelming nature of all the other issues on this forum, this basic info on Cl is frequently overlooked. If you have water that doesn't look good, Chlorine is gonna' be the primary answer the vast majority of the time.

[CAPTCHEMCL]

Thanks Dave. Those who are pool savvy often forget that those of us who are newbies often do not know even the most basic of information. When we got our pool, they put it in and left. No one ever gave us ANY guidance on how to manage it. So when I found this site the other week, I found all the acronyms to be confusing and overwhelming if you don't know anything about the basics. That being said, I am now amazed at how quickly I learned (mostly with the help of Ben's test kit) and our conversion went beautifully, the water is unlike ever before! But it was kind of you to remember that there are some of us who need the basics spelled out to us first! Thank you again.

[bell7272]

Thanks, and great post for those us us just learning about our new pools and water and chemistry.

I'm just starting to use Ben's kit and will now learn about the CYA you discussed. My problem is to high CL, but am lowering the SWG a little every few days until I find a balance.

Thanks again.

[SS 396]

Those who are pool savvy often forget that those of us who are newbies often do not know even the most basic of information. When we got our pool, they put it in and left. No one ever gave us ANY guidance on how to manage it.

I'd have to say the same about us. We bought our pool in 2004 and the place we bought it from went out of business last year. We received no instruction at all so I imagine I'll be asking a few questions, and if they appear to be a dumb question, truth is they are because I have no knowledge on what to do.

Hopefully this forum will educate me, Thanks.

[CarlD]

Well done, Dave!

Two important additions:

1) Chlorine's MOST important target, even more so than algae, is fecal matter--poop. It neutralizes and renders safe the contaminants in fecal matter, the most dangerous pollutant in your pool water. Chlorine is the only sanitizer we can be sure of to neutralize these dangerous contaminants.

When contaminated drinking water is responsible for outbreaks of people getting typhoid, typhus, cholera, etc., the contaminant spreading it is INEVITABLY fecal matter.

2) Stabilizer or CYA, while absolutely necessary, is a two-edged sword. As Dave points out, you must have it to prevent rapid breakdown of chlorine, but too much can prevent chlorine from doing its job. It's very important to use the "Best Guess Table" to determine how much chlorine you need for a given level of stabilizer.

(as an aside, do NOT use stabilizer with indoor pools. Check with PoolDoc on indoor pool management rules)

[duraleigh]

Hi, again,

It is quite revealing that the first two responders to this thread give credit to the Poolsolutions test kit for the understanding they have gained about their pool water.

Folks, that is EXACTLY my source of understanding, too. I knew absolute ZERO about pool water 'til I found this site and got my kit. I have posted time and again about the value of a good test kit and Ben's is the best.

Guessing at the contents of your pool water and asking this forum to guess along with you will prolong your path to crystal clear pool water.

Besides, keeping Ben overwhelmed with Test Kit orders, prevents him from busting me for my frequently short-tempered posts!!

[gonefishin]

Thanks for the post. Being a newbie myself...I'm finding myself always looking for additional information to learn about pool and water maintenance.


I do have a question regarding chlorine and how it interacts with CYA. What is it with "unprotected" chlorine that allows it to be used up by a warm sunny day?

Also...

What is the interaction between CYA and chlorine that seems to protect and stabilize the chlorine in water?

thanks!
dan

[waterbear]

One more thing to add about Chlorine. It's effectiveness is influence by the pH of your pool. Chlorine is only half as effective at a pH of 7.8 then at 7.2! (I will spare everybody the chemistry involved!) This is why pH and chlorine are the two paramters that need to be monitored most closely, perhaps daily, until you learn how YOUR pool operates.

Lot's of good info here, IMHO it should be rewritten into a FAQ and made into a sticky for the newbies (and as a good refresher for the more experienced members!)

[waterbear]

Thanks for the post. Being a newbie myself...I'm finding myself always looking for additional information to learn about pool and water maintenance.


I do have a question regarding chlorine and how it interacts with CYA. What is it with "unprotected" chlorine that allows it to be used up by a warm sunny day?

Also...

What is the interaction between CYA and chlorine that seems to protect and stabilize the chlorine in water?

thanks!
dan

Chlorine and CYA form a type of 'combined chlorine' that is very stable to UV (I believe they form chlorimides) that still has some sanitizing power and tests as FC. If I understand it right only a certain amount of the chlorine combines leaving some FC until the CYA levels get too high for the amount of FC in the water. Don't really know that much about the chemisty involved but I intend to find out now if I can. If I can find out any more info than this little bit that I have found I will post.

[duraleigh]

Hi, again,

I'm on a roll about Chlorine this morning.

I think we could parse this thing to death and, in so doing, may very well detract from the basic info we're trying to convey.

I hope we can keep the peripheral issues at bay (or in a new thread) and let the principles of Cl use in your pool stand alone. (just for this thread)