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Thread: SLAM question

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    SLAM question

    I'm working on my third day and have seen improvement in the water clarity, but FC is still inconsistent.

    My CYA is 40, ph is 7.5, TA 130.

    I'm adding smaller amounts of chlorine, 40 to 60 ounces, trying to get a shock level of 16. An hour after I add I'm still 1.5 points low of my goal. Swings were more exaggerated yesterday. What exactly does a "substantial fraction" represent, phrase taken from Turning Your Green Swamp article. Filter is working fine, backwashing every 8 hours. I've brushed the entire pool each day while chlorine level in the pool is at least at the shock level. When can I come off the Shock level?
    18,000 gal Inground Vinyl Pool, 300lb Sand Filter, Hayward 1hp Single speed pump
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    Re: SLAM question

    Come off shock level when it 8s clear. That being said I really haven't done that to well lately. But it has been over a Month and half for me.

    May/2018 AGP Coleman 24x52 vinyl, 13.6k gallons, Harris H1572228 Vortex 16 inch Above Ground Sand Filter System with 3/4 HP Pump, PoolBlaster Max, TF-100

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    Re: SLAM question

    3 days is nothing. If you continue to see any improvement, keep doing what you are doing. Thoughts:

    - Don't bother to test for anything other than FC / CC until you are done with your SLAM.
    - Don't backwash the filter until the pressure gauge is 25% higher than what it is right after you backwash it.
    - Don't look for consistency in FC loss.
    - Don't go too crazy Test and add a few times a day, not as frequent as every hour (especially after Day 1). And brush once a day, like you said you were.

    The SLAM article has the criteria for ending. Pool School - SLAM - Shock Level And Maintain

    Take a picture everyday if you need convincing that it's getting clearer.

    Edit for clarity. The FC should be tested and added more than twice a day but less than once an hour. Sounded like you driving yourself crazy, what frequency are you testing at?

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    Re: SLAM question

    Quote Originally Posted by Mr Bruce View Post
    3 days is nothing. If you continue to see any improvement, keep doing what you are doing. Thoughts:

    - Don't bother to test for anything other than FC / CC until you are done with your SLAM.
    - Don't backwash the filter until the pressure gauge is 25% higher than what it is right after you backwash it.
    - Don't look for consistency in FC loss.
    - Don't go too crazy Test and add a few times a day, not as frequent as every hour (especially after Day 1). And brush once a day, like you said you were.

    The SLAM article has the criteria for ending. Pool School - SLAM - Shock Level And Maintain

    Take a picture everyday if you need convincing that it's getting clearer.

    Edit for clarity. The FC should be tested and added more than twice a day but less than once an hour. Sounded like you driving yourself crazy, what frequency are you testing at?
    I wasn't as anal the first couple days as I have been today. Been testing FC every hour, but my concern has been that I'm not getting to the shock level after an hour.
    It's actually kinda fun, but I can become as fascinated by the process and trying to interpret that information and lose sight of the evidence that the pool water is improving and that it's working. results
    18,000 gal Inground Vinyl Pool, 300lb Sand Filter, Hayward 1hp Single speed pump
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    Re: SLAM question

    If you are never able to actually get to the SLAM level say after 20-30 minutes after adding with the pump running, it's possible

    a) The chlorine is weaker than you think
    b) Your pool is bigger than you think or
    c) (unlikely IMO) You have a testing error.

    If it were me I would be tempted to aim 1-2 ppm higher for a FC goal just to see what would happen. If in 20 minutes I got a 16 I would raise my pool volume by 2k and work from there.

    Once an hour is too much, unless you just feel like it and don't mind burning through testing chemicals. Once every 2 hours is plenty, most people don't have that kind of time
    32K gallon Plaster - CircuPool SJ-55 SWG - 1hp Hayward 2 speed Super Pump - Hayward S200 Sand Filter - TF100XL/K-1766
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    Re: SLAM question

    Quote Originally Posted by Mr Bruce View Post
    If you are never able to actually get to the SLAM level say after 20-30 minutes after adding with the pump running, it's possible

    a) The chlorine is weaker than you think
    b) Your pool is bigger than you think or
    c) (unlikely IMO) You have a testing error.

    If it were me I would be tempted to aim 1-2 ppm higher for a FC goal just to see what would happen. If in 20 minutes I got a 16 I would raise my pool volume by 2k and work from there.

    Once an hour is too much, unless you just feel like it and don't mind burning through testing chemicals. Once every 2 hours is plenty, most people don't have that kind of time
    My thoughts exactly. Saves me typing.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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    Re: SLAM question

    Thanks for the input.
    18,000 gal Inground Vinyl Pool, 300lb Sand Filter, Hayward 1hp Single speed pump
    Clorox Convert

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    Re: SLAM question

    Several days later and the chlorine demand during the day isn't decreasing, water is much clearer, but still cloudy. I"ll bring it up to shock level at night and it stays within a 1-2 full points between last test at dark and first test before daylight.
    By 12 pm the following day and not adding chlorine since the slab level was ok, the FC level several hours later has dropped 5-6 full points, after bring back to shock level and testing again that evening the FC level has dropped as much as 10 full points. Is this normal? I'm adding 3-5 gallons a day.
    18,000 gal Inground Vinyl Pool, 300lb Sand Filter, Hayward 1hp Single speed pump
    Clorox Convert

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    Re: SLAM question

    Yes. I believe this is normal.

    May/2018 AGP Coleman 24x52 vinyl, 13.6k gallons, Harris H1572228 Vortex 16 inch Above Ground Sand Filter System with 3/4 HP Pump, PoolBlaster Max, TF-100

    Run pump 24/7

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    Richard320's Avatar
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    Re: SLAM question

    Quote Originally Posted by rcs101 View Post
    Several days later and the chlorine demand during the day isn't decreasing, water is much clearer, but still cloudy. I"ll bring it up to shock level at night and it stays within a 1-2 full points between last test at dark and first test before daylight.
    By 12 pm the following day and not adding chlorine since the slab level was ok, the FC level several hours later has dropped 5-6 full points, after bring back to shock level and testing again that evening the FC level has dropped as much as 10 full points. Is this normal? I'm adding 3-5 gallons a day.
    No. Demand should have fallen off by now.

    A few things: can you see the floor, and is there any organic debris still in there?

    Have you carefully checked ladders, steps, and lights?

    Check out the pictures
    Think I may have found my FC demand issue?
    Water problems
    Problem Found and Ideas needed
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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    Re: SLAM question

    I can see the drain covers in the deep end, though not clearly. There's a small amount of silty beige or gray along one of the seam lines that clouds up when I brush.

    The ladder is frozen in the expansion anchors and I can't disassemble, but the outside has been thoroughly cleaned. I'll have to see if I can figure out how to get it apart without destroying the pipe.

    I'll pull the light apart and check.

    Filter seems to be working fine, but it's 4 years old. I've been planning on pulling the filter apart and deep cleaning but haven't, should I?

    I checked out your links, Thanks.
    18,000 gal Inground Vinyl Pool, 300lb Sand Filter, Hayward 1hp Single speed pump
    Clorox Convert

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