no chlorine

Chlorinating, maintaining the right chlorine levels,
chlorine problems. Dichlor, trichlor, cal hypo, bleach,
granules, chlorine pucks and chlorine sticks.
PattyB

No chlorine

Postby PattyB » Mon 08 Jun, 2009 15:04

I also have no Chlorine registering in my pool. Above ground pool, 28 foot round, 20,000 gallons. The hardness is 400 - which shows accurate per my test kit, The PH is at 7.2, The alkinity is 180 - slightly high, the stabliizer is 0. The water is slightly cloudy, it is clearing up. In the past week I have added 7 gallons of liquid chlorine to the pool along with two floats that are always in the pool filled with chlorine tablets. Can someone tell me how do I get the chlorine to register on the test strips? I have tried 2 different packages of strips and nothing is showing. Thanks!


chem geek
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no chlorine

Postby chem geek » Mon 08 Jun, 2009 20:58

Many test strips as well as less expensive chlorine tests (DPD chlorine tests that show pink/red intensity when chlorine is present) will bleach out at high chlorine levels above around 10 ppm. So you could have chlorine in the pool and not know it.

Or you could have a high chlorine demand and possibly a high Cyanuric Acid (CYA) level that makes chlorine less effective (test strips are notorious at measuring CYA incorrectly). I suggest you get yourself a good test kit, either the Taylor K-2006 you can get at a good online price here or the TF100 kit from tftestkits.net here with the latter kit having 36% more volume of reagents so is less expensive per test.

Or it is possible your test strip is correct and that the CYA level is zero in which case chlorine will get broken down by sunlight very quickly -- half of the Free Chlorine (FC) will get lost every half-hour in direct noontime sun. However, with two floaters likely containing Trichlor pucks/tabs, I doubt that your CYA level is zero unless you let your pool go over the winter with zero chlorine (in which case bacteria could have converted CYA into ammonia that then takes a LOT of chlorine to get rid of).
Patty B

No chlorine

Postby Patty B » Wed 10 Jun, 2009 16:54

Thanks for your help. The CYA level is zero from my test strips. The strips I am using is the HTH brand. Everytime I have taken my water to the pool store, this is the same thing they use. From my understanding I have to add stabalizer? We live in IL and have properly closed our pool over the winter. The water color is great, slightly clouldy but I can see the bottom very clearly.
chem geek
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no chlorine

Postby chem geek » Thu 11 Jun, 2009 00:09

Yes, you can add some Cyanuric Acid aka stabilizer or conditioner to the pool. This will protect chlorine from breakdown in sunlight.

By the way, just because the pool store uses test strips does not mean they are accurate. I still suggest you get your own good drop-based test kit.
dwhunker44

No chlorine

Postby dwhunker44 » Sun 14 Jun, 2009 07:00

I also am struggling with a ZERO free chlorine reading. I have had my 28000 gallon pool open for 4 weeks without ever having a free chlorine reading yet. First I was told that a 500 reading of phosphates was the c ulprit. So I bought phosphate and then shocked again a few days later. No more phosphates but still no reading. Then I was told to use see klear mustard algae killer (2 lbs) with calcium hypochlorite (5 lbs). The pool got REAL CLEAR two days later but still no reading. I waited 12 days because I was told this could "mask" a free chlorine reading. I just added 3" pucks for normal maintenance. Finally, the pool turned very cloudy. Now, from my original shocking using 18 lbs x2 times of shock, my CYU was high ~180 and I was told that was my problem. I drained & filled alot of water and now CYU is around 30. PH is 7.2 and ALK is 120 ~ 150. I have a total chlorine reading but still no free chlorine. I pulled out 1 gallon of water and it takes (5) 1/2 tsp of 6% chlorine bleach to change the strip to purple. I read where this means I need to add 100 gallons of chlorine bleach. This seems crazy! Please provide some good advice!! Thanks!
funaquamom

no chlorine

Postby funaquamom » Tue 30 Jun, 2009 22:15

I'm having the same problem. Stabilizer is fine. Pool store says my level of nitrates - 5ppm - is safe but may be enough to consume all the chlorine. Every time. Was advised to drain some water and refill, also have well water tested as it may come from having topped off the pool this season. As this is not a sure thing, I'm going to continue to use algaecide and shock - again - before taking more drastic measures.
chem geek
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no chlorine

Postby chem geek » Wed 01 Jul, 2009 01:03

It's not phosphates and its not nitrates that are the cause of the primary problems. Those would simply be food for algae growth but algae will not consume chlorine as fast as you are seeing. If you add chlorine and it measures as a lot of Combined Chlorine (CC) or if you measure the water with an inexpensive ammonia test kit from a fish/pet/aquarium store and it is high, then the problem is that at some point you let your FC get to zero (perhaps over the winter) and bacteria in the pool converted the Cyanuric Acid (CYA) to ammonia. This can take an extraordinary amount of chlorine to get rid of. There is no other way other than water dilution. Chlorinating liquid or bleach are the least expensive oxidizers to use for this purpose (much less expensive than non-chlorine shock).

However, if your Cyanuric Acid (CYA) level is high, then you'll have to dilute the water anyway to lower it. You can learn more by reading the Pool School. I'd suggest first to dilute the water, then add chlorine (lots of it). Also get yourself a good test kit with a FAS-DPD chlorine test. In the meantime if you have access to an OTO chlorine test (shades of yellow) then this will at least not bleach out so you'll know that you aren't adding too much chlorine.
Nagrath

no chlorine

Postby Nagrath » Sun 27 Sep, 2009 13:38

I'm having a similar problem; pool was beautiful all season; clear, perfect test-strip readings. Was gone for about 4 days and the chlorinator ran out of tabs whileI was away. Opened the pool (it has an automatic cover, which is opaque) and the pool was cloudy white. Shocked it, which did nothing. (it is a 16x36 inground pool - used 2 gallons of liquid chlorine shock once, then again, and then a third time used 4lb granular.); retested---stilll no chlorine, still cloudy. Pool store then tried testing for phosphates - 1000ppm; treated once, got a lot clearer. Treated again, got nicely clear. Have been running the chlorinator on full, but still no chlorine reading on the strips, or at the pool store (they use a photometric tester). What to do? I am testing again to see if there are still phosphates; pool store says they bond to or mask the chlorine. WHat actually is that mechanism? From what I read above, I probably have to put many gallons of chlorine in? I do not use a stabilizer at all--never needed it, pool is kept covered whenever we are not using it; it uses very little chlorine all summer because of that; but now I am running the chlorinator full open, and still zero reading. Help!
Nagrath

no chlorine

Postby Nagrath » Sun 27 Sep, 2009 14:45

A little update to the above post--just had the water retested: zero free chlorine, zero total chlorine, zero phosphates, zero CYA. Have been going through 3"chlorine tabs in my chlorinator, but the level is still zero. just bought stabilizer and 4 gallons of liquid chlorine (12%). Not sure what to do with them. The pool store said I didn't really have to do anything, but I don't like having zero free chlorine. The stabilizer says I should get my chlorine to the proper level before adding it, but I am leaning more toward putting it in first and then adding the liquid chlorine in the hope it will stay around longer. Any help would be appreciated!

John
all blue

no chlorine

Postby all blue » Sun 27 Sep, 2009 17:10

all blue pools here 602-943-1909 35 YS EXPERENCEI AM CURRENTLY WORKING ON THIS PROBLEM. THIS IS STARTING TO NOT BE A RARE OCCURANCE DUE TO THE GREEDYNESS OF THE POOL INDUSTRY, I SAY THIS BECAUSE FIRST THE INDUSTRY PUSHED EVERYBODY NEEDS A SALT POOL , THE LAST TEN YEARS THE PUSH HAS BEEN TREMENDOUS!! NOW I HAVE ADDED SALT TO ALL MY POOLS BUT I HAVE NOT ADDED A SALT GENERATOR (A $1500 EXPENSE TO MY CUSTOMERS) IT HAS TAKEN 3 YEARS OF TESTING AND WORKING WITH ALL MY POOL ACCOUNTS OF OVER 50 POOLS TO DETERMINE THAT
1) OOLS WITH A SALT LEVEL OF 1500PPM -3500 PPM DO BETTER THAN THOSE WITTHOUT
2) SALT IN THE WATER MAKES POOLS ALGAE RESISTANT EXAPLE A POOL IN THE ARIZONA SUN WILL GO 2WEEKS WITHOUT A CHLORINE COUNT,AT92 DEGREE WATER BEFOR IT WILL TURN GREEN
3) IF AND WHEN IT DOES WHEN I SUPER CHLORINATE THE WATER,AND ADD A COPPER BASE ALGACIDE
IT WILL POP RIGHT BACK
4) SALT WILL MAKE YOUR SKIN SO THE CHLORINE WILL NOT CAUSE YOU TO ITCHY AFTER OR DURING YOUR SWIM IF YOU HAVE HIGH CHLORINE LEVELS MAKING IT EASIER TO MAINTAIN A POOL WITH A HIGH CHLORINE LEVEL AND NOT FEEL THE EFFECTS OF IT
5) SALT IN THE POOL WILL KEEPYOU FRO, HAVING RED EYES FROM CHLORINE, AND DRY HAIR WHEN YOU GET OUT.
6) SALT DOES WHAT IS CALLED IONIZES THE WATER CAUSING THE CHEMICALS TO WORK BETTER
SALT WILL METER THE CHLORINE BURN (HOW FAST THE CHLORINE CONSUMPTION IS)IN THE WATER

WHAT IS MY POINT? MY POINT IS IT TOOK THREE YEARS OF "A POOL PROFESSIONAL" WORKING WITHTHE SALT IN HIS CUSTOMERS POOLS TO GET THE TRUTH ABOUT SALT. THE TRUTH IS FOR LESS THAN $100 EVERYBODY CAN HAVE A SALT POOL AND NOT HAVE THE EXPENSE OF THE INSTALL AND THE ,MAINTENANCE OF THE SALT SYSTEM. BUT THIS WAS NOT READILY AVAILABLE INFOMATION AND WHAT I HAVE JUST SHARED IS THREE YEARS OF INTENSE WORK AND KEEPING RECORDS OF MY FINDINGS.

NOW, I SAID ALL THAT TO SAY THAT MOST LIKELY YOUR PROBLEMS EXIST FROM THE PHOSPHATE REMOVER, NOW THAT YOU HAVE ADDED IT. ORIGINALLY, IT WOULD APPEAR THAT YOU HAD A POOL WITHOUT CHLORINE AND JUST NEEDED TO ADD 10 - 15 GAL OF LIQUID CHLORINE. IF I REMEMBER YOU ADDED 4GAL. WHEN A POOL STARTS TO TURN THE POOL STORE WILL GIVE JUST ENOUGH INSTRUCTIONS TO "START" THE POOL ON THE RIGHT PATH OF RECOVERY. I UNDERSTAND AT THE SAME TIME THEY ARE PLAYING IT SAFE. AS A POOL PROFESSIONAL AND WITH THE RATES WE CHARGE IF WE CANNOT TURN A POOL IN 1- 3 DAYS WE WILL BE CONSIDERED "NOT COMPETENT" IN OUR BUSINESS. SO WHEN I TELL YOU 10 - 15 GAL OF LIQUID CHLORINE THIS TO GET THE PROBLEM OVER AND DONE WITH. WHEN ALGAE STARTS YOU MUST KNOW '
1) WHAT IS MY CHEMICAL STATUS ( I NOTICE CHEM GEEK ENCOURAGES "THE LAMOTTE TEST KIT" ALOT OF POOL GUYS USE THIS KIT; IT IS A GOOD KIT I ESTIMATE $25-$35) I DONOT HAVE ONE AT PRESENT BUT DID
TWO IN FACT NOW I USE "AQUA CHECH" WITH THE YELLOW FLIP CAN AND 35YRS OF EXPERIENCE.
THE CHEMICAL BASICS:
WHAT IS YOUR CHEMICALS??
THE AQUA CHECK TEST STRIPS CHECK FOR:
A)FREE CHLORINE; THE WATERS ABILITY TO FIGHT BACTERIA
B)PH); THE ACID CONTENT OF THE POOL TO MUCH ACID WILL CAUSE READING TO BE OFF
C)ALKA;INITY; THE WATERS ABILITY TO BUFFER THE ACID AND KEEP IT FROM ATTACKING THE POOL SURFACE

)C)CYNERIC ACID; THE UMBRELLA OF THE WATER FROM THE SUN AND; AN ACID; AT THE SAME TIME MAKING THE CHLORINE MORE EFFECTIVE AS ACIDS DO, BUT NOT TOO MUCH 7.5-7.6 =EXCELLENT

AND THEN THERE IS ALGACIDES AMMONIA BASED ALGACIDES WILL DESTROY THE CHLORINE LEVEL IN THE POOL WHILE ATTACKING THE ALGAE IF YOU USE AN ALGAECIDE )ONLY WHEN YOU HAVE A ALGAE PROBLEM "NOT" ON A REGULAR BASIS, USE A COPPER BASE ALGACIDE IT WILL NOT AFFECT THE CHLORINE LEVEL. I NOTICED CHEM GEEK REFERRED TO CYNERIC ACID TURNING INTO AMMONIA. I AM GOING TO HAVE TO CHECK THAT OUT. I HAVE NEVER EVER HEARD THAT. TO KILL AMMONIA I HAVE FOUND POTASSIUM PEROXY MONO PERSULFATE, WE USE IT IN THE SPAS A NON -CHLORINE SHOCK APROX $3 A LB,OR LOTS OF LIQUID CHLORINE WHICH IS MADE OF CAUSTIC SODA AND SALT BASED.

NOW THE INDUSTRY IS PUSHING "NO PHOSPHATES"
YOU MUST KILL THE PHOSPHATES! IF IT WERE NOT FOR NEW BLEEDING EDGE IDEAS COMING TO THE POOL INDUSTRY I BELIEVE THE POOL INDUSTRY WOULD GO BROKE " THE OLD ADDAGE "IF IT ISN'T BROKE DON'T FIX IT!" THE CLEAN WATER ACT OF 1972. THE WATER QUALITY ACT OF 1977. AND THE WATER QUALITY ACT OF 1987 ALL MADE PHOSPHATE USE IN DETERGENTS,CLEANING FLUIDS AND ON AND ON TO BE DIMISHED OR TRY TO THE USE OF THEM BECUASE PHOSPHATES WERE ENDING UP IN ALLO OUR LAKES, STREAMS, AND KILLING FISH WILD LIFE ECT.
WHAT IS A PHOSPHATE?? IN LAY MANS TERMS A PHOSFATE IS "ANY PLANT LIFE IN THE WATER"
NOW THE POOL INDUSTRY IS PUSHING "NO PHOSPHATES,NO PHOSPHATES" LETS SEE WHAT DID WE DO FOR THE PAST 100 YRS WITH OUT THIS NEW PUSH?? CHLORINE WORKED JUST FINE. NOW WE HAVE PHOSPHATE REMOVERS WHICH WE HAVE ACTUALLY ALREADY BEEN USING BUT IN THE FORM OF "ALUIM ALUIMUM SULFATE AND ONLY A HAND FUL OR TWO WOULD DO THE JOB TO REMOVE THE FINER PARTICULATES OR TDS-TOTAL DISSOLVED SOLDS FROM THE POOL FOR PENNIES. THERE ARE ACTUALLY 5 SUBSTANCES USED TODAY TO REMOVE PHOSPHATES AND THEY ARE ALSO USED IN THE MEDICAL WORLD.

THE NEW GUY ON THE BLOCK IS #57 "ON THE PERIODIC CHART OF RARE ELEMENTS) LATHANUM. LANTHANUM SULFATE, LANTHANUM CARBONATE. THE POOL STORE AND I WOULD SAY MOST OF THE POOL PROFESSIONALS ARE STILL ON THE LEARNING CURVE ON THIS ONE, JUST LIKE SALT WAS AND THE SALT RVELUTION IS 50YRS OLD NOT THAT NEW.
GO TO PATENT STORM.US AND READ ABOUT "NATURAL CHEMISTRY" US PATENT #6338800 AND READ ABOUT PHOSPHATE REMOVER FROM THE INVENTORS. IT WILL TELL YOU AND I QUOTE
"WHILE THE USE OF SUCH A COMPOUND DOES HAVE CERTAIN BENEFITS, NAMELY THAT THE PHOSPHATE BECOMES BOUND AS INSOUBLE LANTHANUM PHOSPHATE RELATIVELY QUICKLY, IT ALSO HAS CERTAIN DISADVANTAGES. THE INCREASED SOULBILITY OF THE REACTANT ALLOWS IS TO QUICKLY DIFFUSE THROUGHOUT THE AQUEOUS BODY TO WHICH IT IE ADDED. THE AMOUNT OF LANTHANUM THAT IMMEDIATELY REACTS IS LIMITED ONLY BY THE AMOUNT OF AVAILABLE PHOSPHATE, AND BECAUSE THE REATION TAKES PLACE ON A RELATIVELY LARGE SCALE, A LARGE AMOUNT OF PHOSPHATE MAY REACT TO FORM LANTHANUM PHOSPHATE OVER A SHORT PERIOD OF TIME. IN THIS CIRCUMSTANCE , THE INSOUBLE LANTHANUM PHAOPHATE CREATES A VISIBLE CLOUDIND OF THE WATER. AS IT REACTS WITH THE PHOSPHATE, THE INSOULBLELANTHANUM PHOSPHATE PRECIPITATES OUT AS A VERY FINE WHITE COMPOUND. THE PARTICLES FORMED ARE TOO SMALL TO BE REMOVED WITH A " CONVENTIONAL FILTER(SAND), AND "OFTEN" "REQUIRE" SIGNIFICANT EFFORT($$) TO REMOVE. FURTHER, IF AN ""EXCESS"" OF THE COMPOUND IS ADDED , VARIOUS "SIDE REACTIONS" MAY OCCUR, INCLUDING THE FORMATION OF" OTHER PRICIPITATES THAT ARE SIMILARLY DISTRIBUTED THROUGHOUT THE POOL, AND ""DIFFICULT TO REMOVE.""

THAT WAS A MOUTHFUL!! SO, WHAT AM I SAYING?? TOO MUCH OF A GOOD TJING CAN BE BAD AND COMPLICATE THE PROBLEM EVEN WORSE. LANTHANUM COMPOUNDS CAN RESTRICT ALGAE GROWTH JUST LIKE NOT EATING CAN CAUSE YOU TO LOOSE WEIGHT. BUT LANTHANUM DOES NOT KILL ALGAE AND THIS ARTICLE CLEALY STATES THAT ""SANITIZERS"" (CHLORINE) KILLS ALGAE, LANTHANUM ONLY RESTRICTS THEIR FUTURE GROWTH AND TOO MUCH LANTHANUM WILL "MASK" THE CHLORINE READING.. OH THATS REALLY GREAT NOW THAT YOU ADDED LANTHANUM AND THE CHLORINE READIND IS MASKED WHO IS IN CONTROL OF CORRECTING THE WATER BALANCE?? THE POOL STORE?? IT ALL SOUND LIKE CHING$, CHING$.
BEAR WITH ME THE POOL IAM CURRENTLY WORKING ON IS 4 WEEKS INTO THE MAKING WHEN A NEW CUSTOMER OF MINE ENTERED A POOL STORE JUST BECAUSE HE HAD AN ALGAE PROBLEM ALL HE NEEDED WAS CHLORINE AND BAKING SODA, HE HAD A LOW CHLORINE COUNT,LOW ALKALINITY COUNT, AND LOW CYNERIC(STABILIZER) COUNT. NOW $150 LATER AND 8 HOURS OF MY TIME AT AREDUCED RATE OF $10 HR WE ARE ALMOST BACK TO NORMAL.
IN TRYING TO ADD 80Z 0F "ORENDA PR-10000" HE DUMPED 24 OZ OF THE 32 OZ IN THE SKIMMER HE ALSO ADDED CLARIFIERS, AND AMMONIA BASED ALGACIDE( THE $4 A GAL) POOL CHLORINE DESROYER.
OUR READINGS;
FREE CHLORINE=00
PH-7.8
ALKALINITY=60
CYNERIC ACID=40W;
ADDED; 10 LBS TRI-CHLOR POWDER, 24 LBS BI-CARB, 40Z COPPER SULFATE( KILLED THE ALGAE),
10 LBS ISONERIC POWDERED ACID,1 GAL MURATIIC ACID.6 CRUSHED TRI CHLOR TABS56% FROM SHASTA
RESULT;
FREE CHLORINE=10 IN TWO HOURS WAS 00
PH=6.8
ALKALINITY=200
CYNERIC ACID=120
THEN 1 WEEK LATER
10 LBS POTASSIUM MONO PER SULFATE (TO KILL ANY )AMMONIA
1 BOTTLES OF $1 TOILET BOWL CLEANER(WITH LOTS OF PHOPHORIC ACID)
IT IS MY UNDERSTANDING PHOPHORUS WILL ADD LOTS OF PHOSPHATES TO THE WATER TO LOAD UP THE PHOSPHATE REMOVER.
4LBS OF 20 MULE TEAM BORAX (BORON) TO DECREASE ACID
2 SHOVELS OF DIRT MIXED IN WATER (POURED IN THE SKIMMER) TO LOAD UP THE PHOSPHATE REMOVER
7 TRI-CHLOR 56% TABS CRUSHED IN THE SKIMMER FROM SHASTA
THE NEXT MORNING THE CUSTOMER GOT A 3.0 READING WITH HIS DROPS KIT
ALTHOUGH I BELIEVE CRUSHED TABS IN THE SKIMMER WERE STIIL PRESENT AND THE GOOD READING EAS FROM THAT.
TWO DAYS LATER THE POOL WAS BACKWASHED ABD HE IS GETTING A 1.0 READING OF CHLORINE IN THE POOL. MY SPECIAL TAB FEEDER IS IN THE POOL BUT IS ALMMOST EMPTY AND WILL BE RE FILLED OCT 1ST IT CA HOLD 17 TABS AT A TIME AND WILL DIPENSE AT A EVEN RATE FOR SO CHEMS STAY CONSISTENT EVERY DAY WITH ONLY NEEDEING TO BE REFILLED EACH MONTH IN THE SUMMER.
BECAUSE WE ARE NOW GETTING A 1.0 FREE CHLORINE READING I BELIEVE WE ARE ON THE DOWN HILL SIDE OF THE PROBLEM.
IT HAS ALSO BEEN MY EXPERIENCE THAT MINERAL ADDITIVES USED IN SOME ALGACIDES WILL ALSO MASK THE CHLORINE READING. KEEP IT TO THE BASICS. CHLORINE,ACID, ALKALINITY,CYNERIC ACID, SOME SALT,
COPPER BASED ALGACIDES, AND BORAX HAVE FUN! ALL BLUE POOLS 602-943-1909 ALAN ROBINSON :thumbup:[list=][/list]
chem geek
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no chlorine

Postby chem geek » Sun 27 Sep, 2009 22:49

John (Nagrath),

Make sure you are using a chlorine test that does not get bleached out -- a FAS-DPD test is best, but even an OTO test would tell you that the problem isn't the chlorine test. If the test is accurate, then get an inexpensive ammonia test kit from a fish/pet/aquarium store and see if you have ammonia in the pool. If you do, then it will take at least 8x the ammonia amount in chlorine to get rid of -- possibly more (due to intermediate products). You can do a bucket test to see how much chlorine it will take (by scaling appropriately).

It would be strange to have ammonia in the pool if you indeed had no CYA in the pool at all. Note that if you ever used stabilized chlorine (Trichlor pucks/tabs or granules, Dichlor powder) then your pool does have CYA in it. You refer to running the chlorinator full open and usually a "chlorinator" is a Trichlor puck feeder, probably inline. For every 10 ppm FC added by Trichlor, it also increases CYA by 6 ppm so you could have had a LOT of CYA in the water so could, in fact, had bacteria convert it to ammonia when the FC dropped to zero.

Alan,

Please do not use all caps. It is very hard to read.

As for salt pools, there are plenty of salt pools that get algae -- it is not a panacea for preventing algae growth. Even salt pools with a saltwater chlorine generator (SWG) can get algae if they follow the industry recommended FC of 1-3 ppm with a CYA of 60-80 ppm because at 80 ppm CYA you need a minimum of at least 3.6 ppm for the chlorine to kill algae faster than it can grow and given overnight loss a minimum FC of 4 ppm is better in SWG pools with that CYA level. If you want to add something to your pool in a one-time dose with minimal side effects to inhibit algae growth, then 50 ppm Borates would be a better choice. Copper ions (that you mentioned with a copper-based algaecide) are also a one-time dose and definitely can prevent algae, but the metal ions can also stain.

Salt in the pool doesn't affect what chlorine does. The higher salt levels let your eyes not feel as much pressure because the salinity in the pool is higher and closer to the 9000 ppm of your tears. That's all. If your eyes are opened in water with a low salinity, then water tends to enter into the eye creating pressure. There is no mystery here. However, higher salt levels are also more corrosive so there is no free lunch. You can read about some of the problems in this blog though most people are happy with their SWG pools. If you've got soft hardscape stone or less expensive stainless steel or have aluminum such as in pool covers or have metal diving board bases, etc., then you need to be more careful about the faster corrosion.

Salt does not "ionize the water". It does increase what is called the "ionic strength" and that slightly shifts chemical reactions towards the side that has more charged ions because such ions are somewhat shielded, but that's all and it's not a big deal. It doesn't speed up chemical reactions or make things more powerful. It also does not change the speed at which chlorine breaks down from sunlight or other sources, though obviously Cyanuric Acid does that effect in a huge way.

I do NOT recommend the LaMotte test nor test strips. I recommend the Taylor K-2006 kit which can be obtained at a good online price here or the TF100 from tftestkits.net here. These both have the FAS-DPD chlorine test that can measure both Free Chlorine (FC) and Combined Chlorine (CC) accurately to with 0.2 ppm using a 25 ml sample or 0.5 ppm using a 10 ml sample. Unlike DPD chlorine tests, they do not bleach out and can measure up to 50 ppm. They are far more accurate then DPD or OTO tests and test strips (and if LaMotte had a FAS-DPD chlorine test in their kit, then I'd probably recommend that as well). As for test strips, they do not test for Calcium Hardness (CH) -- they only test Total Hardness which is not relevant for calculating the saturation index used to protect plaster surfaces.

Cyanuric Acid (CYA) does not just protect chlorine from sunlight. Though it does absorb UV from the sun shielding lower depths of water, it mostly combines with chlorine to produce chemical (called chlorinated isocyanurates) that are not effective sanitizers nor oxidizers. CYA significantly lowers chlorine's strength and this is very important to know since the FC/CYA ratio is what roughly determines the amount of active chlorine in the water and the amount of chlorine you need to prevent algae growth. See this post for more info on this.

As for phosphates, you are correct that it is not necessary to remove them in order to prevent algae growth. A sufficient FC level relative to the CYA level will prevent algae from growing. Phosphate removes should be seen in the same vein as algaecides -- something that, at extra cost, can lower the rate of algae growth, but not necessary if sufficient chlorine is used. It's more like insurance. You also bring up the interesting true fact that alum flocs also tend to lower phosphate levels (especially very high phosphate levels) though the lanthanum based products are typically used to lower phosphate levels that have already been lowered to at least 1000 ppb by other means.

Though clearing a pool of ammonia can certainly be done with many different oxidizers, including non-chlorine shock (potassium monopersulfate, MPS), it can also be done much less expensively with chlorine alone. As for CYA getting converted into ammonia by bacteria (when the FC gets to zero allowing the bacteria to grow) I describe that here.

Richard
Guest

no chlorine

Postby Guest » Thu 04 Feb, 2010 21:43

mY gOD!!!!...jUST CALL ME i HAVE A PERMANANT SOLUTION AND NO CHEMICALS...NO FEARS...AND NO PATHOGENS......NO ALGAE..NO NOTHING..JUST CLEAN, HEALTHY WATER 24/7 I AM A WATER TREATMENT PROFFESSIONAL...SO I HAVE NO "DOG" IN THIS HUNT! IN OTHER WORDS I AM NOT SELLING POOLS OR CHEMICALS!!!
lbridges
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My Pool: Geometric 16K gal shotcrete w/exposed aggregate; Pentair EasyTouch w/wireless, 2 Intellibrites, VS-3050 pump, C&C 200 Filter, IC-40 SWG; Heliocol solar. Rocky's reel
Location: Space Coast, Florida

no chlorine

Postby lbridges » Fri 05 Feb, 2010 19:56

Pool User wrote:... A PERMANANT SOLUTION AND NO CHEMICALS....


I'm sorry, but I think I have to raise the BS flag for this claim. But I will gladly eat some crow if I'm wrong.
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no chlorine

Postby floridapooltech » Thu 18 Feb, 2010 00:21

It would be wise not to shock the pool as often as your claiming as this will in fact damage the pool's surface. It is possible that you may have over chlorinated your pool to the point a test kit will not register correctly. Another alternative, if however this is not the case, is to add a stabilizer (cyanuric acid) which will slow the rate chlorine will evaporate and lose it's effectiveness. If you have any further questions, feel free to contact our service dept. on the web as we have a "do it yourself" guide filled with tips, advice and tools. We also run promotions for free products, sales, offers & giveaway's.
nagrath

no chlorine

Postby nagrath » Mon 10 May, 2010 12:35

Richard,
It seems that I am still struggling with this problem; I opened up the pool this spring; it was slightly greenish and slightly cloudy; used a Trichlor shock product twice, and the pool cleared up pretty quickly (3-4 days); however, once again I am getting no free chlorine. Pool store tested (using a photometric reader, though I don't know the test they use (it IS a drop test, though), and I came up with ph 7.2, total alk 100, cya 0, free chlorine 0, phosphates 0. How is it I am getting a CYA of zero if I shocked with trichlor and have been using 3" trichlor tabs in my chlorinator? Can the chlorine bleach out the CYA test? I will get the ammonia test; I should have done that last year but did not. Do I correctly understand that I can use regular liquid bleach (if it is unscented) to shock (especially in this case, if I need to add a tremendous amount)? I am nearly at my wits end; the pool looks beautiful, but I get no chlorine reading, even though I smell chlorine when I open the pool. Ugh!

Thank you for all your help; I wish I had followed through on everything last year.

Sincerely,
John

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