Chloramines & their affect on
your spa, hot tub and swimming pool
The following information was found at
another website which we agreed to purchase because it is well written and
understandable. We think you will find it interesting as well as
of the most common causes of water related problems in swimming pools is the
presence of chloramines. Chloramines are often referred to as
“combined-chlorines” because they are molecules formed by the combination of
chlorine in the form of Hypochlorous Acid (HOCl) and organic wastes (saliva,
perspiration, urine) in the form nitrogen or ammonia. Chloramines produce
the “chlorine odor” that many people do not like (tear gas is a form of
chloramine). When people complain of “too much” chlorine, it is always the
case of combined chlorine or chloramines causing the foul odor.
foul chlorine odors are just the ugly mask of the underlying problems
present in swimming pool water.
Chloramines are the root of a lot of problems in pool water. Chloramines
cause problems because of their stability and persistence. This stability
and persistence forms additional Chloramines. This is chlorine demand
(consumption) at its finest. (Consumers complain that they “just shocked”
the pool but there’s no chlorine showing when tested.) As more chlorine is
added without reaching breakpoint, more chloramines are formed exacerbating
the problem leading to what I’ll call “obvious problems” such as cloudy
water or algae growth. Homeowners and/or pool dealers unfamiliar with
chloramines and chlorine demand begin treating the symptoms (cloudy water or
algae) rather than dealing with the root cause – especially after the second
or third treatment. Without the knowledge of chloramines & chlorine demand,
consumers may not receive the help they need.
Chlorine demand testing stations aid greatly in determining the appropriate
amount of chlorine needed to reach breakpoint chlorination – usually
recognized as 10 ppm FAC (free available chlorine) to correct each 1ppm of
combined chlorine. Failing to realize this amount actually contributes to
the chlorine demand problem as more chloramines are formed. We often hear
the consumer complain that “my pool guy told me to put in a double dose of
shock to treat my cloudy pool.” That amount may indeed fall VERY short of
the actual need. When a chlorine demand test is performed, it is often seen
that a dose of 10, 20 or more times of chlorine shock is needed to reach
breakpoint chlorination. That means potentially adding 40, 50 or more
pounds of shock (in the form of cal hypo) at one time -- Yes, at one time.
If you try spreading it out (even over a few hours) you’ve defeated the
describe the problem this way to our customers in regards to reaching
breakpoint: Reaching breakpoint chlorination is an “all or nothing”
proposition. Think of it as trying to jump the Grand Canyon in a single
bound; you can’t “come close”. You MUST reach the other side FIRMLY. You
can’t “almost make it.” Whether you’re 2 inches short or 100 feet short,
you’re still short.
This is where our constant reminding of consumers of the need to weekly
shock their chlorine or bromine pool. Weekly shocking during the entire
time the pool is open & operating will greatly reduce the potential of
chlorine demand or consumption.
Another facet to the chlorine demand and chloramines problem is the
misconception that the pool “smells of chlorine”, therefore (in the novice’s
mind) “I’ve got too much chlorine or too many chemicals present in the
water, “ and they stop adding anything to the pool, effectively ignoring the
problem. Testing goes out the window; pH and overall water balance go out of
balance. The pool owner is not convinced that their true problem is a
“lack” of chlorine and particularly FAC. This is especially true if the
homeowner or pool operator is using OTO (will produce results for Total
Chlorine only, using yellow color standards, not differentiating the
difference between FAC and chloramines present) for chlorine testing as
opposed to the more accurate DPD (using pink color standards) method (tests
for Free Chlorine as well as Total Chlorine).
Controlling small amounts (under 2.0 ppm) chloramines is relatively easy.
Shock the pool with a good-quality granular chlorine or use an oxidizing
compound containing potassium mono-persulfate. Mono-persulfate “shocks” are
great because they don’t add additional chlorine that may contribute to
further chloramine formation. We have found that even when there are larger
amounts of chloramines present, the mono-persulfate works well in reducing
the chloramines by oxidizing these wastes and releasing the combined
chlorines. Breakpoint chlorination often-times becomes simpler to achieve.
Again, weekly shocking of the pool is the preferred preventative procedure.
Just because the pool water looks good doesn’t mean that very thing is
balanced and working properly.
A lurking problem?
Another potential area or source of the chloramine problem may be something
we as dealers or homeowners have no control over. The following comments
and questions that I pose are purely speculative and have not been
scientifically proved. My premises are based on over 30 years of
experiential observation and hopefully common sense. The chloramine
problems that we’ve been discussing in this article have become more
prevalent each passing swimming season over the past decade. There’s a
greater frequency and severity of the chloramine issue.
the early and mid 1990’s, the nation’s public water suppliers began
switching to using chloramines in the water sanitizing process. Chloramines
were and are known to be more stable and “persistent” as we’ve already
mentioned. Chloramines due a good job controlling normal bacteria and
“stuff” in water. I will not discuss the reasons why chloramines are the
preferred and even mandated form of bacteria control in potable water
systems. That is a discussion for the scientist and politician. As a
layman, I am looking at my daily observations.
Throughout the 1990’s we heard the cry of “get of rid of chlorine!”
Chlorine was given a bad rap. Mainly from people who don’t know what
they’re talking about. After all, how do you ban an element? People didn’t
like the so-called taste of chlorine in their drinking water. Given a choice
of coli-form bacteria or a slight chlorine taste, I’ll take the chlorine
taste. Chlorine has undoubtedly saved thousands, and I dare say millions, of
lives around the world in purifying water. We see what untreated water
looks & smells like and its devastating effects. This is especially
poignant in the wake of Hurricanes Katrina and Rita.
These are my observations over the past 10 - 15 years regarding swimming
pools: Increasing frequency and severity in treating chloramines in
swimming pool water; Increased questions of chlorine demand or consumption;
More frequent consumer complaints of skin rashes or eye irritation when
using a pool, spa or hot tub. In the late 1980’s and early 1990’s, “pink
slime” and “white water mold” were being blamed on biguanide usage, until it
was noticed that there was this pink stuff coming from the garden hose.
From a potable drinking water standpoint these are my observations. Tap
water rarely “smells” of chlorine. A need to more frequently clean my
bathroom or sink areas. The toilet always seems to have a ring. Often
times when the garden hose is turned on, a “glob” of icky, pink stuff comes
out. What’s going on?
we tell our pool or spa customers to run the water for a minute or two to
flush out the garden hose before adding that water to the pool, spa or hot
tub (now we’re “wasting water,” a very valuable resource. We don’t want the
“bio-film” in the pool or spa, but what about the chloramines coming in? Do
we have a potential situation where pathogens, that may be present in the
drinking water, are being killed but then their “waste” is not being
oxidized? Why is there a build-up of bio-films in garden hoses, sinks,
chloramines good oxidizers? No. As pool & spa professionals, we know the
necessity and advantage that regular oxidation performs; we more fully get
rid of ALL of the stuff that is a potential contaminant. I base my
hypothesis on the fact that if you add more chloramines to pool or spa
water, you will form even more. It’s a vicious circle.
pool, spa or hot tub owner and user must understand these facts and act
accordingly to protect not only his or her investment, but also the health
of the users.
there a correlation? In my opinion, possibly. Unfortunately, it will take
many years of testing & “scientific” observation before we have a conclusive
the meanwhile, the local public water suppliers tell us: “Chloramines will
not affect swimming pools; you will still need a free-chlorine residual to
retard algae and bacterial growths in pools.” (http://www.casitaswater.org/water%20utility/chloramines.htm
the same time, in the same article, there is the statement that “[a] small
amount of ammonia used to form Chloramines may affect rubber and some
manufacturing processes. Chloramines may cause rubber linings of water lines
to disintegrate over a period of time.”
Other comments published by other water authorities such as in Pasco County,
Florida, provide similar information. (http://pascocountyfl.net/utilities/water/Chloramine.htm)
there a matter of public health? I don’t know. I have not investigated nor
do I have the specific expertise to probe those more far-reaching
consequences. Over the years I have tended to trust, almost without
question, our public officials. I believe they are constantly doing what is
in all of our best interests. I believe this because they have families and
loved-ones who are drinking this water also.
purpose in writing this article is to simply address some possible
correlations that may directly affect my customers’ pools, spas & hot tubs
and their families and friends who
use them. People in both the pool & spa industries and public health &
water supply need to work together to address these issues. Although the
“use” of water for filling pools and spas is relatively small (practically
speaking), our impact is great across the country. Consumers are constantly
looking for answers to simply their pool and spa care needs and expense.
Consumers also want to be assured of their personal health and safety
regarding both swimming, soaking and drinking.