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Thread: Pool will not clear FC 0 TC 10

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    Pool will not clear FC 0 TC 10

    My pool is cloudy and will not clear it is 18 x 36 inground about 27000 gallons. I threw in 3 pounds of cal hypo and didnt get a reading so today i dumped in 8 gallons of liquid chlorine and 4 hours later FC is back to 0 and TC is around 10. My ph and alk are perfect and my CA level is around 25-40 ppm. HELP!!
    Jessica (first time pool owner)
    NE Texas
    Intex Ultra Frame UG 12x24x52; 8,500 gallons
    Intex 1600 Sand Filter (SF15110)
    Intex Saltwater System (CS8110)

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    Mod Squad jblizzle's Avatar
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    Re: Pool will not clear FC 0 TC 10

    Welcome to TFP!!

    What are you using to test the FC and CC (we do not really care about the TC = FC+CC) levels? Are you suggesting that your CC are 10ppm? That would be unusuably high and could suggest the presence of something (ammonia) in the water that will require a lot of chlorine to remove.
    Jason, TFP Moderator
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    duraleigh's Avatar
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    Re: Pool will not clear FC 0 TC 10

    Welcome to the forum. You are not adding enough chlorine to your pool and you are not HOLDING the high level of chlorine needed to clear your pool.

    read "The ABC's of Pool Water Chemistry" up in Pool School and then read "SLAM - Shock Level And Maintain" in the How To section of Pool School.

    If you follow the SLAM process precisely, your pool will clear.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

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    Re: Pool will not clear FC 0 TC 10

    Has your cyanuric acid level recently dropped?

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    Re: Pool will not clear FC 0 TC 10

    Im using aquachek 7 strips to test. TC is between 8-10 FC 0 . My cyanuric acid level was around 120 earlier in season so I added lots of fresh water to get it back down to around 20
    Jessica (first time pool owner)
    NE Texas
    Intex Ultra Frame UG 12x24x52; 8,500 gallons
    Intex 1600 Sand Filter (SF15110)
    Intex Saltwater System (CS8110)

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    linen's Avatar
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    Re: Pool will not clear FC 0 TC 10

    Welcome to tfp, jlock2013

    Test strips in general can't be trusted and they are almost always wrong when measuring cya. See this pool school article for an appropriate test kit: http://www.troublefreepool.com/pool-...kit_comparison

    What kind and size of pool do you have? Better yet put your pool and equipment details into your signature.

    Since we do not know what cya level you have (assuming the cya measurements were from the strips?), then we really don't know what FC level you need to get to in order to do the SLAM process properly. So getting a accurate value for cya is the next step.
    TFP Expert who uses Pool School and my TF100 test kit along with PoolMath for my: Round 11K gallon AGP with deep end, 20" sand filter, Matrix 1hp 2spd, 6 2ftX20ft solar panels (and solar cover!), Intex SWCG (copper bars disconnected) and a Rubadub hot tub (chlorine). The SLAM process is not finished until: 1. CC < 0.5 ppm, 2. An OCLT < 1.0 ppm and, 3. The water is crystal clear.

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    Re: Pool will not clear FC 0 TC 10

    Ok I brought water into pool store for a test. This morning the CC is 1.5 and FC is .11 my cyanuric acid is reading 5 . They use a waterlink lamotte spin disk test. I was told to put in about 5 pounds of cyanuric acid into skimmer and put in 8 gallons liquid chlorine. Does that sound right?
    Ive been dumping chlorine for a week with no results.

    18 x 36 27000 gallons . Sand filter ( changed sand last year)/ vinyl liner pool . 1.5 hp super pump
    Jessica (first time pool owner)
    NE Texas
    Intex Ultra Frame UG 12x24x52; 8,500 gallons
    Intex 1600 Sand Filter (SF15110)
    Intex Saltwater System (CS8110)

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    Mod Squad JohnT's Avatar
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    Re: Pool will not clear FC 0 TC 10

    Your problem is very, very simple. You aren't putting in enough chlorine and you aren't adding it often enough. SLAMing Your Pool It wouldn't be unusual to need to add more chlorine an hour after adding it the first few times.
    TFP Moderator
    20K Gallon 20X36 Vinyl Inground
    Hayward S244T Sand Filter with 1HP Whisperflo Pump. Liquidator C-201 and Solar Heat

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    Smykowski's Avatar
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    Re: Pool will not clear FC 0 TC 10

    I really want to help you, but I'm leery of giving advice without test results we can trust.

    CYA of 5 doesn't really make any sense. Anything between 0 and 20 will come back as anything between 0 and 20. If that number is correct, 5lbs of stabilizer brings you up to about 30, which would be correct.

    Are they saying add 8 gallons of 12.5%, or 8 gallons of 8.25%? Either way, it's overkill.

    Again, all of my comments are based on the (probably incorrect) assumption that those results can be trusted.
    33' round, 23,000 gal AG vinyl , 1HP 2spd PowerFlo Matrix downsized with 3/4HP impeller (X2), Hayward S180T 150# sand filter (X2), Hayward H250 NG heater Pool Store year 1 - $850 for 2 months; Pool Store year 2 - $440 for 2 months, TFPC year 1 - $170 for 4 months; TFPC year 2 - $95 for 4.5 months
    The most important article on this site - The ABCs of Pool Water Chemistry

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    Re: Pool will not clear FC 0 TC 10

    12.5 % liquid chlorine
    Jessica (first time pool owner)
    NE Texas
    Intex Ultra Frame UG 12x24x52; 8,500 gallons
    Intex 1600 Sand Filter (SF15110)
    Intex Saltwater System (CS8110)

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    Re: Pool will not clear FC 0 TC 10

    I just dumped in the 8 gallons and I have another 8 on hand if or when I need too
    Jessica (first time pool owner)
    NE Texas
    Intex Ultra Frame UG 12x24x52; 8,500 gallons
    Intex 1600 Sand Filter (SF15110)
    Intex Saltwater System (CS8110)

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    Donldson's Avatar
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    Re: Pool will not clear FC 0 TC 10

    Well, your FC is now somewhere around 37. If your CYA really is below 20 a very large portion of that is going to burn away in the sunlight today though.

    The SLAM Process
    Higher FC levels will oxidize contaminates more quickly, but levels that are too high can cause damage to the pool or the pool equipment. Recommended shock levels are designed to break down contaminates reasonably quickly while posing minimal risk to the pool. It is impossible to know in advance just how much chlorine will be required to SLAM the pool. Instead, chlorine is added to maintain shock level until testing shows that the process is complete.
    JD - 28' Round Above Ground Pool, 17,000 Gallons. Dual speed Jacuzzi pump with cartridge filter. Dual speed 1 HP pump, Hayward S210T sand filter
    Pool School - PoolMath - HIGHLY Recommended Test Kits

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    Re: Pool will not clear FC 0 TC 10

    so should I keep adding liquid? I have 8 gallons left. 5 lbs of CYA in in skimmer
    Jessica (first time pool owner)
    NE Texas
    Intex Ultra Frame UG 12x24x52; 8,500 gallons
    Intex 1600 Sand Filter (SF15110)
    Intex Saltwater System (CS8110)

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    linen's Avatar
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    Re: Pool will not clear FC 0 TC 10

    I know this is frustrating for you, but we don't know if you should keep adding the liquid, since we don't know what your current FC level is.

    When adding cya during shocking, it is best to put in an old sock and hang it in front of the pool return (water coming back into the pool) since you can't clean your filter right away.

    I agree that the cya of 5 seems unlikely. What is the history on your pool in terms of using stabilzer (cya), trichlor and dichlor? All of those add cya.

    You need to get one of the test kits mentioned in the link above. This will help you be efficient with the SLAM process and know what your pool needs for normal maintenance too so that you will not have to do the SLAM process again.
    TFP Expert who uses Pool School and my TF100 test kit along with PoolMath for my: Round 11K gallon AGP with deep end, 20" sand filter, Matrix 1hp 2spd, 6 2ftX20ft solar panels (and solar cover!), Intex SWCG (copper bars disconnected) and a Rubadub hot tub (chlorine). The SLAM process is not finished until: 1. CC < 0.5 ppm, 2. An OCLT < 1.0 ppm and, 3. The water is crystal clear.

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