Can I have "milder" Chlorine levels with SWG?

tnthudson

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Mar 31, 2008
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Central VA
#1
Hello,
I have had Baquacil in my pool for two seasons, but plan to open as a Chlorine pool this year. Trouble is, myself and my son break out in alot of pools that have Chlorine.
So my question is, can you have "lower" or "milder" levels of Chlorine in a SWG pool? I would like to have a safe, sparkling pool, of course, but if we break out too much, it's kind of a waste. My impression from reading about SWG pools is that they may be "easier" on some swimmers with sensitivities; is this true?
Thanks!
 

JasonLion

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May 7, 2007
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#2
There are three main effects related to sensitivities from a SWG. First the salt in the water helps some people. You don't need to have an SWG to use salt but none the less the effects of salt are associated with SWGs in people's minds. Second, a SWG makes it much simpler to maintain uniform chlorine levels, even when you fail to pay attention. With uniform levels there are fewer problems and so less likelihood of CC or other issues. Third, a SWG usually allows you to run the pool with slightly lower chlorine levels. No one is sure just why that is, but in practice the FC level can be a little lower with a SWG.

Of these effects, the salt is the most obvious. Many people comment that it improves the feel of the water on your skin and reduces skin irritation. The slightly reduced chlorine levels seem to be least important. If you have a true chlorine allergy then normally even small amounts trigger it . There is still chemically identical chlorine in the water with a SWG, even if in slightly lower amounts.
 
G

Guest

#3
To add to what JasonLion said, a SWG allows you to run a lower FC for the level of CYA that is recommended for a SWG compared to the level of chlorine for the same CYA level in a manually chlorinated pool. Most SWGs recommend a CYA level of around 60-80 ppm and seem to be trouble free as long as the free chlorine is maintained at about 4 ppm. In a manually chlorinated pool with this CYA level you would need to maintain a FC of at least 6 ppm to maybe 9 ppm to avoid problems.
Most salt pools never or very rarely need to be shocked and don't seem to have a problem with combined chloramines forming.
HOWEVER, you will not be able to run lower FC levels and get away with it. If you install an ionizer, either active or a passive 'mineral' system line Nature 2 (I would NOT recommend either) you can get away with keeping the FC at 2 ppm but not any lower if you have a SWG.
 

tnthudson

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Mar 31, 2008
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Central VA
#5
Thanks!
I did have 2 more quick questions (for now, at least - ha!)
1. If I'm understanding right, I may be able to get by with 4ppm Chlorine with a SWG, but not lower, right?
2. What about pets? We just got two Golden Retrievers, and I understand they LOVE pools...is it safe for them to get in/drink the water?
thanks again!
 
G

Guest

#6
It's never a good idea to let your pets drink from the pool but a small amount of pool water should not hurt them. Swimming is fine. You CAN train dogs (AND cats) not to drink from the pool. I know...I trained my three dogs and my cat not to.

As far as the chlorine levels go, we have found out that 4 ppm FC with 60-80 ppm CYA leads to just about as close to "maintenance free" water as you can get with a SWG. (You will still need to monitor your pH, TA, CH, salt, CYA and Borates, if you use them, however).
 

JasonLion

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#7
It is possible to set things up to allow somewhat lower FC levels, as low as 2 ppm in some cases, by running at lower CYA levels, but it does require an oversized SWG, shortens your SWG cell life noticeably, requires the pump to be running during the day, and causes some other complications. I would never normally suggest trying any such thing, and I very much doubt that you will need it, but if it makes the difference between swimming and not swimming it might be worth looking into.
 

JasonLion

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#9
Leeman, welcome to TFP!

The ideal FC level to use with a SWG depends on several factors, but with default assumptions 4 ppm is a very reasonable target. The desired FC level depends on the CYA level. With CYA in the ideal range of 60-80, FC should be no lower than 3 ppm. It is best to go a little higher than that, thus 4 ppm, just in case something happens that sends you down below your normal level. If you run a SWG with lower CYA levels you can use lower FC levels, though various problems come up, such as shorter cell life, etc. If you use 50 ppm of borates you can often go to slightly lower FC levels.

Going below the recommended FC level doesn't automatically cause problems right away. Often you can go weeks or months at lower levels without a problem, but then something will go wrong. For example, some storms put more than the average amount of organic debris into the pool and that can allow algae to get started. My recommendations are designed to give you a trouble free pool, rather than something that usually works but occasionally has problems.
 

tnthudson

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Mar 31, 2008
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Central VA
#10
Great suggestions! Thanks again JasonLion and Waterbear, I think I'm starting to catch on a little.
Waterbear, I may have to open a new thread in a couple of weeks on training pets not to drink from a pool :? , these guys are 4 1/2 mo. old and they are feisty!
 
G
#11
Well, I have a Yorkie, Miniature Schnauzer,and a long haired Daschund. If you know anything about any of these breeds they all share a common characteristic. They are stubborn :shock: when they want to be but I was able to train them :whip: to not drink from the pool. My cat still needs an occasional reminder so I keep a filled water gun near the pool. (The cat actually loves water and has even gotten into the shower with me so he thinks the watergun is just a game but it does divert his attention from drinking from the hot tub spillover or the deck jets.)
 

chem geek

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Mar 28, 2007
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San Rafael, CA USA
#14
If one has Borates in the pool, then it's best to not have dogs drink it regularly. Even without borates, an SWG pool with 3000 ppm is salty and represents 3 grams of salt per liter of water. It is recommended for people to not have more than around 3 grams of salt per day though the U.S. average is more like 5-6 grams. Fortunately, unlike people, dogs and cats are apparently able to excrete excess salt (in their urine) without causing heart problems or high blood pressure. So if you find a person drinking pool water, train them to stop. :shock:
 

JRM

Member
Apr 12, 2008
8
0
#15
Chemical effects on pets and humans

tnthudson wrote about his and his son's chemical sensitivities and Chem Geek wrote:
If one has Borates in the pool, then it's best to not have dogs drink it regularly. Even without borates, an SWG pool with 3000 ppm is salty and represents 3 grams of salt per liter of water. It is recommended for people to not have more than around 3 grams of salt per day though the U.S. average is more like 5-6 grams. Fortunately, unlike people, dogs and cats are apparently able to excrete excess salt (in their urine) without causing heart problems or high blood pressure. So if you find a person drinking pool water, train them to stop.
This brings up a question I've been pondering. There's lot's of discussion about various chemicals and combinations of chemicals to use to maintain crystal clear low-maintenance water, control algae, reduce phosphates, eliminate scaling, etc. etc. And theres even some discussion about effects on pets drinking the water. But what about effects on humans? My kids (and I) spend hundreds and hundreds of hours in the pool every summer and swallow (and absorb) no small amount of pool water; which of these chemicals, in what concentrations, are safe or unsafe for human consumption? What are the long term effects of various exposure levels?

Not really expecting definitive answers here, but I think this is a topic that merits more discussion and attention and that should be addressed in the promotion of and information on the various pool chemicals.

John
 
G
#16
As far as borates go they are a common ingredient in 'bath salts', the chlorine in drinking water is often higher than in pools, and the only algaecide you really need is chlorine. Lineaer Quats are somewhat toxic (they are basically the same as many common antibacterials sanitizers such as found in barbershop sanitizers, antiseptics like Bactine, and cream rinses because they are substantive to hair. Copper sulfate can be toxic in high doses, Polyquat is probably the least toxic but realize that algaecides are meant to kill something! So is chlorine. CYA has a very low toxicity in humans so it's not a worry in the levels found in pools (I know there is some hype about it being cyanide but that is, to put it mildly BULL ****! (Sorry Sean if this is not appropriate but I need to get across how wrong this is. This is usually one of the scare tactics that the ionizer companies use (I won't mention any one in particular that would not be Smarte! ;) ) You are exposed to MUCH higher chemical levels if you go in the ocean, BTW!

Chlorine is the safest santizer we have at this point in time and is fairly innocuous when used in pools. Ditto for the other chemicals, remember you are not drinking pool water. The little bit you might swallow is not going to hurt you.