► In-Line Chlorinator And Check Valve?

I have an in-line chlorine feeder.  Do I need to use a check valve if there is no heater?

Nameless, 2/10/2008

The purpose of the check valve is to protect the heater from corrosive backflow from the chlorinator.  No heater, means a backflow valve is not required.  Not having a heater might give you pause to think about SolarPills.  This product helps keep the water warmer, by reducing evaporation.  I hope that this answers the question.

Sincerely.  Alan Schuster, 2/11/2008

► More Than Mellow Yellow?

Hi Alan, Love your website, I couldn't really find an answer to my question, can you help me?  We have had our new pool for 3 years (new home). We have a good filter system, etc. and the water has been fine, but recently the chlorine levels are really high. My husband added shock a few times, because a friend said that would help, but I actually think that is when the problem started. We only do the "visual" test, don't know how to do all the numbers. The color is bright orange, instead of mellow yellow. We turned off our chlorinator, and waited over a week, and it still is high. The pool gets very little use, just us, about once a month.  Any suggestions?  Thanks.

Cheryl, St. Augustine, FL, 2/20/2006

Too much chlorine - plain and simple.  The tester that you are using provides a poor picture of the state of the chlorine content.  I suggest that you get a test strip such as the LaMotte Insta-Test.  It measures free and total chlorine.  The free chlorine should be 1-3 PPM and the total chlorine not more than 0.3 PPM higher, for ideal conditions.  A water analysis will help determine what the next step should be.  If the free chlorine is low, add more chlorine.  If the total chlorine is more than 1 PPM, try adding some potassium monopersulfate shock. Hope that I have been helpful.

Sincerely.  Alan Schuster, 2/20/2006

► Unstabilized Tablets & Reducing Cost?

Can you tell me who makes/sells unstabilized chlorine in tablet or stick form. I generally use 3" pucks but they seem to only be available with stabilizer in my area (Tennessee). Some guy on a forum, which I can't find again, said he had started using unstabilized tablets because of stabilizer build up and that's what I need to do. I have used liquid bleach and it's good, but  it has gotten as expensive as pool stuff and it's heavy.  Thank.

Mac, Gallatin, TN, 1/10/2008

► Why Test Total Chlorine?

Found you site through the LaMotte website.  I recently bought a Pool Manager DPD test kit (model DT-3, Code 7011). I am a new in ground pool owner in the south of France. I am OK with the pH test (5 drops of indicator) and the free Chlorine test (add tablet 1 to fresh water), but it is unclear whether the total chlorine tablet goes in the same water as the free chlorine test (i.e. sequential) or whether I need to get some fresh water from the pool.  I am aiming for a target of 1.5/2.0 Free Chlorine and 7.4 pH, are there any limits for the Total Chlorine and why am I doing this test at all?  Best regards.

Edward M., France, 8/27/2005

You should use the same water sample.  The Free Chlorine test measures the active sanitizer.  Total Chlorine is Free Chlorine plus Combined Chlorine.  Ideally, you want the Total Chlorine reading to be less than 0.3 PPM higher than the Free Chlorine reading.  Otherwise, a shock treatment may be necessary.  Combined chlorines are irritating and odorous and you want to control their concentration.  I hope this explanation helps.

Sincerely.  Alan Schuster, 8/27/2005

Can you please tell me a chemical I can use to make chlorine last longer in the hot sun.  Thanks.

Noeline T., New Zealand, 1/15/2010

Chlorine stabilizer is what you need to help make chlorine last longer.  Chemically, it is cyanuric acid.  It is sold, most wherever pool chemicals are sold.  In most cases 20-40 PPM is used.  Chlorine depletion can also be due to algae growth, high bather use, urine, phosphates and nitrates.  Poor circulation can make algae growth more likely.  You might consider adding THE CIRCULATOR. I hope that this information will prove helpful.

Sincerely.  Alan Schuster, 1/16/2010

► Chlorine Overproduction? 

Our pool has a salt water chlorinator.  I don't actually add chlorine to my pool.  We use test strips which indicate high Free Chlorine. Can you give some suggestions on what we should do to drop the chlorine level?

Josephine S., Australia, 4/18/2005

You are producing too much chlorine for the pool, at least for this time of the year.  Lower the setting on your salt chlorine generator or cut back on the hours of usage.  Chlorine neutralizer products are available that can quickly lower very high levels.  Otherwise, shut off the chlorine generator, until the level drops into a comfortable range.  I hope that this information proves helpful.

Sincerely.  Alan Schuster, 4/18/2005

► Lightening The Load?

Hi Alan: I have a small inground pool and it holds about 10,000 gallons of water.  I have been putting in 2 x 3 inch tablets a week and one 2 1/2 gallon jug of liquid chlorine.  I am getting older now and having a hard time with the jugs as they are getting to heavy for me.  Is there anything that I could replace the liquid chlorine with once a week that may be easier?  I bought some small packages of super chlorinate granules and it says for 10,000 gallons of water.  Would that do the trick?  Thanks a lot.

Dick, 4/7/2003

Basically, you were supplementing the chlorine tablets with a once-a-week shock treatment using the liquid chlorine.  You can use a granular chlorine or shock for the same purpose.  The tablets have a low pH and the liquid chlorine has a high pH.  They tended to cancel each other out.  Switching to another product might require that you pay more attention to the pH, depending upon the nature of the product.  I hope that I have been helpful.  Enjoy the pool season.

Sincerely.  Alan Schuster, 4/7/2003

► Dark Orange Test Color?

We just opened our 24 foot round above ground pool.  I did not check the chemicals before adding 2 gallons chlorine and 18oz of algaecide.  Now, 24 hours later, when I check the chemicals, the chlorine reading is dark orange and pH is very dark red.  What do I have too much or too little of?

Pam, 5/17/2004

Sounds like you are using an OTO test kit.  The dark orange color should indicate that the chlorine level is very high.  If you just opened the pool, it will drop as the chlorine reacts with algae and debris.  The very red color probably indicates that the pH is too high.  Add pH reducer, in order to lower it into the 7.2-7.6 range.  OTO test kits present a, somewhat, misleading picture of the state of the pool water chemistry.  I suggest that you consider using a more modern product such as Insta-Test Test Strips.  These test strips function well at high ranges and test for the more important Free Chlorine reading.  OTO only test total chlorine.  I hope the information proves helpful.

Sincerely.  Alan Schuster, 5/18/2004

► Why Does The Chlorine Level Drop?

I’m using a salt water generator on a 34,000 gal indoor pool that I keep covered.  I use the ColorQ test kit for all testing. I keep the pH at 7.2, The stabilizer is 68 ppm, so the alkalinity is 81 (alkalinity tests at 109 ppm), free chlorine at 2 to 3 ppm, total chlorine less than 2 ppm over the free chlorine. Recently, the chlorine is being used up at a rate of about 1 ppm per day, even if no one uses the pool. Why is the chlorine getting used up do fast?  Thanks,

Arthur K., Crystal Lake, 12/15/2008

Your combined chlorine (the difference between the free and total chlorine readings) is too high.  Ideally it should be under 0.3 PPM - certainly under 1 PPM.  In your case the reading could be 2 PPM.  Each 1 PPM of combined chlorine will destroy 10 PPM of free chlorine, which is why the level is dropping.  When the combined chlorine gets under 0.3 PPM, the free chlorine level should be more stable.  In addition,, the filter contains organic matter, which was previously filtered out.  As water passes through the filter, it reacts with this organic debris.  There could be a little or a lot.  When the filter is off, bacteria, in the filter are free to grow, creating a new demand for chlorine.  When the filter and pipes are free from organic matter, the chlorine stability should increase.  I hope that this information has been helpful.

Sincerely.  Alan Schuster, 12/15/2008

► Chlorinator Not Working Right?

I have a chlorinator unit located right beside the pool filter, with an access lid at the top. It has an open pvc pipe in the middle where water flows down the pipe and out into the pool.  I can’t see where the water is being pumped or pushed into the unit.  My problem is there doesn’t seem to be adequate water being pushed up into the unit to sufficiently erode the 3” chlorine tablets.  The flow of water leaving the unit and going into the pool is slower than normal.  Is there anything I can do to fix this?  I use to keep 3-4 tablets in the unit and maintained chlorine/free chlorine levels at 3 and 3.  Now, I put 6 or 7 tablets in and I can barely keep a 1 PPM level.  No algae in the pool yet!  Help!

Marie M., 8/11/2005

It sounds like the chlorinator has become clogged with scale deposits or product residues, although I can't be certain.  I suggest that you refer to the troubleshooting guide that may be present on the manufacturer's website.  Before attempting to clean this equipment, all chlorine must be removed.  Good luck and I hope that this information proves helpful.

Sincerely.  Alan Schuster, 8/11/2005

Thanks for the quick response.  You were right.  The inlet line was clogged.  We’ve fixed it and things are back to normal.  I’ll definitely recommend your site to others!  Thanks again!

Marie M., 8/12/2005

► Chlorine:  is it Free or Total?

I am going to a fitness club to swim in San Diego area.  I am unable to do any other exercise because of severe back problems.  Every time I go home after a swim and dip in the hot tub, my skin burns and gets prickly hot and I can't get the smell of chlorine out of my sinuses for 2 days.  I talked to the maintenance man who said the he keeps the pool at 3 PPM and the hot tub at 5 PPM with a pH of about 7-7.5.  Is he keeping the chlorine levels too high, especially in the spa?  I desperately need to get this resolved so I can continue my only form of exercise without developing a skin problem on top of my many other health problems.  Thanks.

Lori B., San Diego, CA, 2/15/2005

There are two types of chlorine:  free chlorine that is the active germicidal form and combined chlorine which can be odorous, irritating and ineffective.  The combination of free and combined chlorine is total chlorine.  Most often the free chlorine is maintained at 1-3 PPM and the total chlorine should not be more than 0.3 PPM higher than the free chlorine reading, for ideal conditions.  There is no way for me to know if the operator is testing for free or total chlorine.  I suggest that you ask some questions, as to what is actually being tested, being maintained and what the county health authorities require.  Maintaining such a facility solely on chlorine is fast becoming a thing of the past.  Today, salt chlorinators, ozonators, uv sanitizers and other alternative sanitizers are becoming the rule, rather than the exception.  Good luck and I hope that I have been of some help.

Sincerely.  Alan Schuster, 2/15/2005

► Combined Chlorine In Tap Water?

Is there a test that can be done to check for "Inorganic" vs. "Organic" combined chlorine.  It is my understanding that some combined chlorine may be present, in the tap water, in the inorganic form.  It is, also, my understanding that this "Inorganic Chlorine" cannot be broken down by superchlorination (10 x the combined chlorine level).  Is this true, and if so is there another way it can be eliminated?

Mike C., 4/16/2004

Never been asked this before!  It is true that there may be some combined chlorine present in some municipal water supplies:  chloramine to be more precise.  While chloramine is much less effective as a sanitizer, than is chlorine (hypochlorous acid), it is also unlikely to oxidize some simple organic contaminants into chlorinated hydrocarbons (chloroform for example).  For this reason many water authorities use chloramine instead of chlorine.  In any event, we are dealing with very low quantities, especially as compared to the concentrations found in a swimming pool.  Chloramine can be destroyed by 10 times its concentration of chlorine.  Your question centers on inorganic vs. organic and in that context there is a problem.  An organic compound is defined as one that contains both carbon and hydrogen.  Chloramine does not contain carbon and is not an organic compound.  If you are trying to read something sinister into the presence of chloramine in your water supply, you are off the mark, as its presence is likely intentional.  I hope that I have answered the question. 

Sincerely.  Alan Schuster, 4/16/2004

► Standard For Chloramines?

► Stabilized Chlorine & Indoor Pool?

My name is Josh of Hampstead, MD. I am a lifeguard and certified pool operator at a local indoor pool and have a question for you. We recently switched our chlorine treatment from sodium hypochlorite (liquid chlorine) to sodium Dichloro-S-Triaznetrione (dichlor). And the other day read that you should not use this in indoor pools. The reading did not give a reason why and I have been searching the Internet, but cannot find an answer.  Can you help me?

Josh D., Hampstead, MD, 4/5/2004

Shouldn't, don't need to or can't!  Provided that state laws do not prevent the use of stabilized chlorine in commercial pools, you can certainly use sodium dichlor in an indoor pool.  However, you are paying a premium price for a chlorine that is stabilized against UV light from the Sun.  This is not an issue in a indoor pool.  The better question would be, should I use sodium dichlor?  And the answer is no!  The use of sodium dichlor would cause the cyanuric acid level to rise steadily over time, forcing at least a partial replacement of the water on a regular basis.  The advantage of dichlor is that it is essentially neutral and completely soluble.  Liquid chlorine can be metered in continuously and provide more controllable sanitation.  It will require the regular addition of acid to maintain the pH.  It is by far and away the most popular chlorine for use in commercial pools.  I hope that this information will prove helpful.

Sincerely.  Alan Schuster, 4/5/2004

► Stabilized Vs. Unstabilized?

Hello, Alan.  I have a 18' x 4' above ground vinyl pool.  I have been given different advice from everybody about what type of chlorine I should use.  Stabilized vs. Non-Stabilized!  Some say that stabilized will "eat" away the vinyl.  While others say that because I used non-stabilized is the reason why I had so many problems last year with high pH and mustard algae!  I am confused on which is best.  Can you please help? I don't want to go through all that again this year!  Thanks. 

Shannon, 5/8/2003

Stabilized chlorine will not "eat away" at vinyl liners.  If you leave any kind of chlorine in prolonged contact will vinyl, it can affect the color or damage the surface.  When you use the unstabilized products, the chlorine level spikes upward and slowly drops, due to bather action, debris and the Sun's UV rays, until you add more.  In addition, unstabilized chlorine products are all high pH and will raise the pH each time they are added.  High pH values, tend to make the chlorine less effective.  The combination of high pH and depleted chlorine levels can lead to algae problems, such as you are describing.  If you are using calcium hypochlorite, the hardness levels will build up, over time, and may result in cloudy water and/or scaling conditions.  Stabilized chlorines fall into two categories:  a quick dissolving, completely soluble and essentially pH neutral granular dichlor and the slow dissolving solid forms of trichlor.  Trichlor is acidic and will require periodic adjustment of the pH.  The advantage is that this product can be used in a feeder, providing a more consistent application of chlorine to the pool.  This, in turn, helps to reduce the probability of algae growth and makes for more comfortable swimming conditions.  Stabilized chlorines are protected against UV destruction and tend to last longer than unstabilized types.  The best defense against mustard algae is maintain a consistent free chlorine level, of 1-3 PPM, and use an effective algaecide, as additional protection.  I hope that I have answered your questions and provided some assistance.  Enjoy the pool season,

Sincerely,  Alan Schuster, 5/8/2003

► Cyanuric Acid Contribution?

► Lowering Pool Chlorine Level?

The chlorine level in my pool is through the roof and I can't figure out how to lower it,  I have heard that I should use muriatic acid to lower the level?  If that's true how should I go about it?  Thank you for your help             

Dalton, 3/9/2005

It is not true!  It will make the chlorine more aggressive and could fade the liner.  Keep the pH at 7.2-7.6.  Lowering the level is simple.  All you have to do is add a chlorine neutralizer product, as directed.  It will work quickly.  In the future remember that you can always add more chlorine - you can't take out.  Good luck and I hope that I have been helpful.

Sincerely.  Alan Schuster, 3/10/2005

► Still Good?

I have some 3" chlorine tablets that I bought in bulk that are about a year old. Are they still good?  Also I live in Houston, TX where it get very hot (95 - 100 degrees) in the summer and my pool is exposed to the western sun. I had problem maintaining a chlorine level of 1-3 as recommended. The chlorine seem to evaporate from the water in a day due to the temperature. I have a 22,000 gallon gunite pool and the chlorinator dissolves my chlorine tablets at about a rate of 7-8 tablets a week. Any thoughts on that matter. Thanks.

Ken S, Houston, TX, 1/8/2004

It is possible that the chlorine has lost some of its strength over time.  Short of a chemical analysis, there is no way to be sure.  Your apparently high chlorine consumption could be related to the biological demands of the water, the high temperatures, sun exposure and possibly the pool water chemistry.  It may have nothing to do with the content of the tablets.  I suggest that you shock the pool to eliminate any pent-up chlorine demand and start with a level playing field.  Unless the tablets are in a state of obvious deterioration, I would certainly use up the tablets.  In the unlikely event that their potency is reduced, you should add an extra tablet, monitor the chlorine readings and adjust the chlorinator accordingly.  I hope that I have been helpful.

Sincerely.  Alan Schuster, 1/9/2004

► Chlorine Block?

Alan, is there such a thing as over chlorinating a pool? Is it possible that I added too much shock?  My pool is extremely cloudy and I have been trying to shock it  and it does not seem to be working.  the filter has been running for four days now, and still cloudy.  I have backwashed it, added clearing chemical, and vacuumed it twice.  Is it possible I have a chlorine block going on?  If so, how do I treat it? Thank You.

Rod Nelson, 10/8/2003

Chlorine block is one of those swimming pool water problem areas riddled with myth and misinformation.  If the pool has been over chlorinated, the test readings should be very high.  The catch is that very high chlorine levels can destroy the testing chemicals and give false results.  The best method to use to test for high chlorine levels is Syringaldazine:  the chemical used in test strips such as the Insta-Test products.  Do you have high chlorine levels?  My guess is that you do not.  I suggest that you confirm what your free chlorine level is and if it is below 5 PPM, you should add more shock.  It sounds like you have a sand filter and this type of filter can be less effective after backwashing.  Inadequate filtration is probably part or all of the cause of the cloudy pool water.  Boost the free chlorine level to 10 PPM and add 1/2 pound of DE to the skimmer with the filter operating.  Make sure that the pH is 7.2-7.6 and keep the filter running.  The next day add a dose of a quality blue clarifier, to help coagulate fine, suspended particles.  Once the water is clear, backwash to waste and reapply the DE.  Thereafter, backwash only when the pressure is too high.  The efficiency of a sand filter can be greatly improved by the use of zeolite sand replacement filter media.  It is convenient, longer-lasting and modestly priced.  Something to consider, whenever the filter sand is replaced? I hope that this information will prove helpful.

Sincerely.  Alan Schuster, 10/8/2003

► Needing A Lifesaver?

Alan I am ready to throw in the towel. I have a approx 24,000 gal. inground pool.  I just had a new pool liner put in and I used my well to fill up the pool.  I can not keep a chlorine reading for more than 2 days. I have add chlorine stabilizer though I'm not sure I added enough. I keep getting algae growth on a continuous bases.  The pH is within limits and so is the TA. I have to shock the pool ever 3 days to keep a reading at all and it drops fast.  I also keep chlorine tablets in the skimmer this does not help either. This is getting expensive. Another question how do I test for calcium hardness I have never done this.  Starting from scratch with new (well)  water what are all the chemicals I have to add for the water to be correct.  Maybe I missed something?  Any information would be a life saver. Thanks.

Lori from Carolina, 9/13/2003

Not having enough stabilizer is not the problem!  Your pool has algae and you are not going to be able to maintain a Free Chlorine level, that is adequate, without destroying all of the algae.  To do this you must add a quick dissolving chlorine or shock, every few hours, until the algae is gone and you are able to maintain a 1-3 PPM Free Chlorine level, after an overnight period.  Keep the filter running and try to redirect the returns to send more water towards the problem areas.  Your well water could contain materials that consume chlorine or add to the problem.  If possible. have the water tested for phosphates and nitrates.  Both are possible, if the well is from an agricultural area.  Test kits or test strips are available that test for calcium hardness, as other pool water parameters.  I would suggest that you add a quality mineral treatment, as soon as possible, because well water can contain metals that can color the water and stain underwater surfaces.  Refer to the archives on pool shocking, pool water testing and algae for additional information.  I hope that I have been helpful.

Sincerely.  Alan Schuster, 9/13/2003

► Needing A Bit More?

I have an automatic chlorinator and it doesn't always seem to provide enough chlorine.  I have opened the settings all the way.  A few times the water started to cloud.  Any advice will be helpful.

Hank A.  Columbus, OH, 6/18/2003

Try and keep the chlorinator filled with the tablets.  Don't wait for them to dissolve half way or more.  The more chlorine in the chlorinator - the more that will dissolve.  Try shocking the pool every Sunday evening.  The weekend is usually the most active period and the shock treatment will help re-establish the Free Chlorine level.  That way the chlorinator does not have to play catch up.  These suggestions should help, just make sure that you test for Free Chlorine regularly and often.  Enjoy the summer.

Sincerely.  Alan Schuster, 6/18/2003

► Wanting To Protect The Liner?

Todd in Alabama, 4/25/2004

Chlorine should always be added in full accordance of the label directions.  Adding chlorine through the skimmer is not something that filter manufacturers recommend or that I would ever suggest.  I assume that the product that you are referring to contains sodium dichlor.  Dissolving this product in a bucket of water could prove dangerous and that is the reason it is and should used in that manner.  This product is normally broadcast into the pool and is relatively quick dissolving.  Your concern about the liner is well founded.  Avoiding chlorine contact with the vinyl liner is a good practice.  Because you are using trichlor tablets, in a feeder, I suggest that you use a product other than dichlor, as a shock treatment.  Otherwise the stabilizer level will rise too rapidly, possibly requiring some water replacement.  This can be done by using liquid chlorine or a non-chlorine shock, whenever a shock treatment is required.  Avoid ultra high free chlorine levels, especially coupled with low pH conditions.  I hope that this information is helpful.

► How To Neutralize Chlorine?

► What Is Stabilized Chlorine?

Can you explain to me what stabilized chlorine is and what are the advantages and disadvantages?  Right now I am using calcium hypochlorite and I'd like to switch.  Thanks.

Jason F., Oakdale, NY, 5/11/2003

Stabilized chlorine refers to products that help protect chlorine, in the water, from being destroyed by ultra-violet rays from the Sun.  This ability will help the chlorine last longer and save on consumption of chlorine.  Stabilized chlorines are essentially chlorinated cyanuric acid.  It is the cyanuric acid portion that acts as a stabilizer or conditioner and improves the performance of these types of chlorine.  Stabilized chlorine is available in two types.  Sodium dichlor is a granular material, completely soluble, quick dissolving, essentially pH neutral and is used for daily chlorination and shock treatment.   Sodium dichlor cannot be used in an enclosed chlorinator. Trichlor is usually available in a solid form, tablets or sticks, and is a slow-dissolving product, that is used in chlorinators and floating feeders.  A granular form of trichlor is available for spot treatment of masonry pools only - not for use in vinyl pools!  Trichlor is acidic in nature and its use may lower the pH over time.  Stabilized chlorines offer versatility and convenience.  The only disadvantage is that the stabilizer level can build up over time and can require some replacement of pool water.  I hope that I have explained the product.  Enjoy the summer.

Sincerely.  Alan Schuster, 5/11/2003

► Various Names For Chlorine?

Everything I read has a different name for chlorine and it's confusing.  Free chlorine?  Is that something that you don't have to pay for?  Just kidding, but you can get the drift?   Could you explain the differences in really simple terms.  Thanks.

Cliff L., Brockton, MA, 6/30/2005

Chlorine does have a variety of descriptive names, as follows:

Free Chlorine is the active germicidal form of chlorine and chemically known as hypochlorous acid.  Also called Available Chlorine.  This is the good stuff, as far as sanitizing is concerned.

Combined Chlorines are the products formed when Free Chlorine reacts with waste materials and forms Chloramines and other Combined Chlorines.  These forms can cause odor problems and are irritating and ineffective pool water sanitizers.

Total Chlorine is the sum of the Free Chlorine plus the Combined Chlorine.  This value includes all the forms of chlorine.  Sometimes, called Chlorine Residual. This is not a meaningful indicator of the sanitizer level, because you never know how much is Free Chlorine.

Chloramines are irritating, odorous forms of combined chlorine, formed by the reaction of chlorine with nitrogen containing waste products.  Ineffective as a pool or spa sanitizer.  High levels of chloramines can cause the problems of "Red Eyes" or Stinging Eyes."   Usually requires a shock treatment to lower or destroy.

If you are only going to perform one test, do the  Free Chlorine Test.  In ideal swimming pool water, the Total Chlorine reading should not be more than 1 PPM higher than the Free Chlorine reading.   That can be difficult in the real world, so be prepared for occasionally higher differences.  I tried to keep it simple.  Hope I succeeded!

Sincerely.  Alan Schuster, 6/30/2005

► Chlorine Age?

I have been told by my pool serviceman that the age of chlorine makes a huge difference.  Is this true?  I could buy chlorine much cheaper, but the suggestion is too stick to fresh chlorine. What is the word Alan, you are the guru.

Todd S., 9/22/2003

► Should I Dissolve The Chlorine?

I have been dissolving granular chlorine in a plastic bucket before adding to the pool.  Is that a good practice?  My friends say no.  Please settle the question for us.  Thank you.

Cynthia W., Pottstown, PA, 7/23/2004

I'll side with your friends!  What you are doing, depending upon the type of chlorine used, could be quite dangerous.  Please read the labels and follow the directions.   Please! 

Sincerely.   Alan Schuster, 7/23/2004

► Protecting The Vinyl Liner?

A friend of mine had a beautiful looking above ground pool, just a few years ago.  Now the liner looks all bleached out.  He adds a granular chlorine to the pool and just dumps it into the water.  I'm not sure, but I think the chlorine is the problem.  Can that be?   I am doing some research now because I plan on getting a pool next spring and I would like to maintain the appearance.  Thanks.

Jason A., Worcester, MA, 10/5/2004

It is normal for a vinyl liner to lose some of the color over a long period of time.  Ideally, it happens on an even, overall basis and not in blotches.  Vinyl liners can last for 10-20 years, depending upon vinyl quality and conditions,  before needing a replacement.  The practice of "dumping" chlorine into the pool is not helping to preserve the liner's appearance.  Granular chlorine should be broadcast across the surface, to allow for a more gentle addition to the water.  This will avoid clumping on the bottom, which could result in some bleaching.  Chemicals should be added with the filter operating.  If there is an automatic pool cleaner, it can help avoid products remaining on the bottom, by improving circulation across the depths of the pool.   Typically, lithium hypochlorite and sodium dichlor are added to the pool by broadcasting.  Calcium hypochlorite is usually added by forming a slurry and decanting the clear liquid into the pool:  away from the walls and in front of a return flow. Always use all chlorine products in full accordance with the label instructions!  Built-in chlorinators, that use solid forms of Trichlor are very popular and help avoid liner fading, by applying a more uniform concentration of chlorine over a period of time.  Salt Chlorinators avoid the need to add any chlorine at all.  The chlorine is made right in the pool and it can maintain a much more consistent level - something that's good for a vinyl liner.  Or you could add an Ozone Generator or a UV Sanitizer and it can drastically reduce the amount of chlorine that you will have to add and the liner will look all the better!  Good luck with the pool.  I hope that I have been helpful.

Sincerely.  Alan Schuster, 10/6/2004

► Gas Chlorine?

Gas chlorine seems to getting more popular.  You don't have to handle any chlorine and the price is right.  Any thoughts on this topic?

Rob T., Lewisville, TX

I don't like any method that adds all the chlorine, at one time.  Gas chlorine certainly can be effective and does not contribute byproducts, but there is a downside, in my opinion.  The chlorine level spikes upward, because of how it is added, and that can compromise bather comfort and bleach bathing suits.  In the case of vinyl pools, the color of the vinyl liner could fade at an accelerated rate.  I am a believer in the type of prolonged or slower-release chlorination that can be obtained by using an automatic chlorinator or a salt/chlorine generator.  These methods are better at keeping the Chlorine level within the 1-3 PPM range, that is so important for comfortable and worry-free enjoyment of the pool.  I hope that I have been helpful.

Sincerely.  Alan Schuster

► Tablets In The Skimmer?

We had an 18X36 vinyl inground pool installed this season.  I have been using the "hockey puck" tablets in the skimmer.  I was familiar with the method because of how my parents maintained their pool.  A friend mentioned, that this is not a good method, and suggested that I get a chlorinator.  Is that the case?  Thank you.

Billy, 7/23/2003

It does sound like a case of like father like son!  There are a host of reasons that you should not be following this practice.  Some filter manufacturers will frown on this chlorination method.  If you have a heater, it can lead to heater damage.  At the very least you are exposing your vinyl liner to fading.  Picture this:   after the pump shuts off the chlorine tablets continue their slow dissolution and raise the chlorine level in the skimmer.  Convection and currents can carry this higher chlorine content water out of the skimmer and into contact with the liner.   Given enough time, there can be a degree of liner fading, especially in the areas surrounding the skimmer containing the chlorine tablets.  If you add an automatic chlorinator, I'm sure that you will find that your use of chlorine will decrease because it is not being consumed in your filter and that you will have more control over the chlorine level.  And of course your vinyl liner's appearance may be saved.  Browse through the archives for more information on chlorine, filters, heaters and liners.   I hope that I have been helpful and convincing.

Sincerely.  Alan Schuster, 7/23/2004

► Chlorine Floats?

I have an in ground vinyl pool, 16 by 32 with a 6' deep end.  I see all sorts of fancy devices for sanitizing.   I use 1" trichlor tablets in floating feeder and shock the pool weekly.   It all seems to work for me.  What am I missing? 

Michael  N.,  Penfield, NY, 8/2/2004

I suspect that you are someone that is taking the time to do all the maintenance.  Obviously you are doing a good job.  Unfortunately there are lots of pool owners that don't spend the time to test the water, add the chemicals, vacuum the bottom and clean the filter.   Basically, you are satisfying the pools requirement for chlorine.  However, there are a few limitations.  The floater gives your less control over the rate of chlorine additions and probably makes monitoring more frequent.  But, these are things that you can work to control.  However, there is something that you cannot correct and that is the floater itself.  The floater remains in the water at all times and can be carried by currents or winds to positions behind pool ladders or into corners.  Here it can remain in prolonged contact with the liner's surface and this can result in a bleaching of the vinyl liner.  Using a floating chlorinator in a vinyl pool can entail a risk of bleaching and can be avoided by using an inline chlorinator.  The inline chlorinator makes chlorine additions simpler, more controllable, helps avoid liner damage and takes the chlorine floater out of the pool and away from the bathers and that is a good thing!  I hope that I have been helpful.  Enjoy the summer.

Sincerely.  Alan Schuster, 8/2/2004

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